ASVAB Math Study Guide

Our ASVAB Math study guide encompasses the simple to complex nature of mathematically-inclined concepts including fractions, percentages, certain math properties, basic algebra, exponents, and logarithms. Do take your time to thoroughly read each topic and understand the given examples.

What kind of math is on the ASVAB?

Our ASVAB Math study guide encompasses the simple to complex nature of mathematically-inclined concepts including fractions, percentages, certain math properties, basic algebra, exponents, and logarithms. Do take your time to thoroughly read each topic and understand the given examples.


Multiplication of Fractions

Try to recall these simple fractional terms:

asvab mathematics knowledge study guide

Where the variable above the fraction is called the Numerator and the variable below is called the Denominator.

To try this out, let’s try multiplying these fractions:

asvab mathematics knowledge study guide

We first multiply the numerators and then the denominators to find the answer. 

Take Note:

Try to always reduce the result to its lowest possible terms. Given this example, both numerator and denominator don’t have common factors thus, this fraction can no longer be reduced. 

Division of Fractions

For example:

asvab math study guide

This can be done by changing the division sign (÷) into a multiplication sign (×) and then reciprocating the second number.  

asvab math

Like the example given above, this case cannot further be reduced.

Mixed Fractions 

A fundamental way to deal with mixed fractions is by turning it into an improper fraction which is a different kind of fraction that has a greater numerator than the denominator.

Supposed that we have this mixed fraction:

asvab math mixed fractions

We can convert it through the multiplication of the whole number(3) with the denominator(4) and subsequently, adding the product of the latter with the numerator( 3).

asvab math mixed fractions

As a result, the denominator from the first mixed fraction will be the same as the improper fraction. 

Improper to Mixed Fraction Conversion

As we see from the preceding examples, we’ve converted a mixed fraction (known as mixed number) to an improper fraction. But now, we’ll learn about the reciprocal of the matter. 

Let’s try this example:


We can simply convert it by dividing the numerator with the denominator. 

asvab math mixed fractions 3

Meaning, we first divide 7 with 12 resulting in 1 then bring down 5. After this, you’ll put the remainder which is 5 beside the quotient (1) in a fraction manner as a numerator and retain the denominator which is 7. 


The percentage formula is utilized when expressing a number between one and zero. More so, it is used to know the parts of a whole in a more specific way. Denoted with the symbol (%), it is primarily used to determine and compare the ratios.

Percentage(P) = (IV ⁄ TV) × 100, where IV is the initial or pre-given value and TV is the total value.

Sample problem:

In a singing competition, there are 20 contestants. Out of them, 11 are boys. Determine the percentage of boys in the said contest.


Total number of contestants in the class = 20

No. of Boys in the competition = 11

% of boys in the competition = (11 ⁄ 20) × 100 = (1100 ⁄ 2000) = 0.55 or 55%

Basic Properties of Numbers

Generally, there are four properties of numbers: associative, commutative, identity and distributive. Such properties are important rudiments upon advancing to a higher level of mathematics.

Associative Property

Addition: When two or more numbers undergo addition or multiplication, regardless of the way they are arranged, the sum will remain unchanged.

5 + (4 + 1) = 10 or (5 + 4) + 1 = 10 

Commutative Property

Multiplication. When two numbers undergo multiplication or addition, regardless of their group, their product or sum remains the same.

 8 x 6 = 48 or 6 x 8 = 48

Identity Property 

  1. Addition and Subtraction. The sum and difference, respectively of any value with zero being that number

5 + 0 = 5 , 5-0=5

  1. Multiplication and Division. The product and quotient of any value with one being that number. 

15 x 1 = 15, 15/1= 15

Distributive Property

 This property entails the solution in an expression such as a(b + c) or literally following the PEMDAS rule.

 3 x (4 + 5) = 27 or 3 x 4 + 3 x 5 = 27


It is the study of mathematical symbols along with rules encapsulating variables with distinct contexts and is also referred to as the backbone of mathematics.

Solving for x in a Basic Equation

Oftentimes, we get to solve x in every exam or test given by our teacher or professor. Basically, the main objective is to get the value of x through ‘reverse PEMDAS manipulation. In other words, whatever is done on the left side, will also be performed on the right side of the equal sign. 

Sample Problem:

x + 7 = 10

With this, we are trying to determine the possible x value that when subtracted to 7, will have a difference of 10. This may be logically easy but we’ll try getting the x value by itself. For that to happen, we have to remove 7 from the left side by subtracting 7 on both sides. 

x + 7 = 10

x + 7 – 7 = 10 – 7

x = 3

Determining the x value in an Inequality Equation

The solving process in finding x in equality is similar to an inequality. One thing it differs is that, through division or multiplication by a negative value, the direction of the inequality’s sign changes. 

Sample Problem:

2x + 20 ≥ 40

Like equality’s first step, we start by subtracting 20 on both sides.

2x + 20 ≥ 40

2x + 2  −20 ≥ 40 −20

2x ≥ 20

After that, we then divide 2 into both sides. The inequality’s direction remains unaffected due to the fact that we’ve divided it with positive value. 

x ≥ 10


Generally, it involves two numbers and is used when multiplying a number by itself. More so, it is stated as “a raised to the power of n” or aⁿ

One example is, 6 cubed:

= 6 x 6 x 6
= 216

Next example, 7 squared:

= 7 × 7
= 49

Take note:

A value raised to the power of 1 equals itself such as 51= 5 x 1= 5, itself

A value raised to the power of 0 equals 1 such as 70 = 1

You can simply subtract the exponents whenever the base is the same such as

95 / 93
= 95-3
= 92

To check:
95 = 9 x 9 x 9 x 9 x 9 and 93 = 9× 9× 9
95 / 93 = (9 x 9 x 9 x 9 x 9) / (9 x 9 x 9)= 9 × 9 = 92

Square Roots

To put it simply, the square root is the mathematical inverse of taking a square root, meaning —square root “nullifies” squared values.

Let’s try, 4 squared or 42

42 = 4 × 4 = 16

To put it into perspective, we can figure out what number is necessary to be squared, when we successfully determine the square root of a given number, 

Advice: Try asking yourself, “What numerical value squared could give us the given value such as 16?


Logarithm denoted as log(x) serves as the function in contrast to exponentiation, and is referred as the power to which a given value must be raised to obtain the necessary rate. It is widely known as a math operation that figures out the frequency or number of times a certain value termed as a base, undergoes multiplication by itself. It is also used in various statistical methods that track arithmetic processes in a particular mathematical context.

Common Logarithms

Mathematically, these are types of logarithms limited to base 10. 

Also written as:

asvab math Common Logarithms

Natural Logarithms

It is a special form of logarithm in which the base is a constant e, where e is an irrational number. The natural log of a number x is written as:

asvab math Common Logarithms

Take note that, ln is the inverse of e.

Negative Logarithms

Logarithms don’t usually settle with negative values but this serves as an exemption, such that all values situated between 0 and 1 are deemed as negative algorithms.

Our ASVAB Mathematics Knowledge study guide and free ASVAB math knowledge practice test will help you understand thoroughly the problems in this area. You can retake our practice test unlimited times to boost your knowledge and confidence. 

Take more of our ASVAB practice test for other areas to cover all ASVAB knowledge.

ASVAB Electronics Information Study Guide

Our ASVAB Electronics Information Study Guide including general information from basic electrical symbols and functions to electrical wiring and the like.

Our ASVAB Electronics Information Study Guide including general information from basic electrical symbols and functions to electrical wiring and the like. This is among the general topics encapsulated in the ASVAB Electronics section. It’s worth noting that some topics may seem familiar but it is very essential to study further about the basic electronic configurations such as how circuits operate, the electric current’s primary definition, conductors, and circuits along with the utilization of Ohm’s law. 

Relatively, such sections of the study guide consist of varying questions on analytical vocabulary, and the ability to intuitively recognize simple electrically-inclined concepts. Bear in mind that upon studying the ASVAB electronics study guide, do magnify more on the very foundation of the topic and avoid neglecting even the simplest conditions as this would substantiate the concept definitions which would be mentioned in the succeeding sub-topics and outlines of the study guide. 

The information below will show you some basic concepts you may meet in your ASVAB electronics test.

Concept of Flowing Electrons

Like an electric current, this describes the manner with what concurrently occurs upon noting an excess of electrons that moves from the negative origin (−) to an area that has a deficit in electrons commonly known as the positive origin (+). Subsequently, the flow of electrons is reflective of the repulsive and attractive forces between varying charged components.



It is a path that permits electricity to flow from one area to another. Regardless of consisting electrical components, the flow remains unobstructed by a break or gap in the circuit. More so, through utilization conducting materials, along with insulated wires, attached to and connecting both terminals forms a certain circuit. 

A prime example that embodies a simple circuit is a battery-based flashlight. Upon pressing the ON button switch of the flashlight, it allows interaction between two contact strips, which initiates an electrical flow, conducted from the battery. The batteries are connected in such a way that the charges from the batteries then flow to the bulb eventually lighting it up.


Open and Closed Circuits

The components of a closed circuit are connected which allows the flow of electrons through conducting wires or materials towards a voltage sequence. On top of this, a gap in the circuit may hinder the connection to properly function. In simple terms, an open circuit won’t work while a closed circuit can. 



It is an electrical component or part of a circuit that drains electric power. This includes home appliances that harness electricity. Load may also be denoted as the power consumed by a circuit. It is the opposite of a power source as a load only dispels charge from a circuit but doesn’t yield power.


Series Circuit

It is a type of circuit that consists of a single path in which the whole current traverses through one component to another. It is only through each linear component in the series circuit where the current would categorically flow. More so, series circuits have the same current that runs through each component in the process. 

The sum of the circuit’s resistivity is the sum in each component’s voltage drops and is the sum of the total voltage and total resistance in a series circuit, respectively. Equivalent resistance which is denoted by Req is the sum of each resistance in the circuit. Considering that there is only a single currency in the process, the term Req is usually used in calculating series circuits through Ohm’s Law.


Parallel Circuit

This type of circuit comprises multiple paths in which the current passes through. With that separation of paths, the current’s power may vary. Regardless of the separated paths, the voltage drop remains the same across the remaining branches. 

Unlike a series circuit, if a gap or break is observed in a parallel circuit or simply disconnected, the division will not hinder the current to pass through the other branches.

The parallel circuit’s equivalent resistance is exemplified as:


where 1Req and R1 to R3 serve as the equivalent resistance, first resistor, second resistor, third resistor, and so on. 


Electrical Power

It is a quantified scaling of the degree of work made by a circuit through a unit of time. Along it is formulas that calculate the electrical power dispersed or produced in the process such as:




in which P is Power, I is Current, R is Resistance, and V is Voltage. 

Take note that, it is the voltage source where power is generated and subsequently, dissipated by consisting loads.


Electrical Units of Measurement

Amperes—measures electrical current.

Ohms—measures resistivity. 

Watts—measures electrical power. 

Volts—measures voltage. 

Metric Prefixes

nano- is 110^−9, micro- is 110^-6, milli- is 110^−3, centi- is 110^−2, kilo- is 110^3 and mega- is 110^6, and giga- is 110^9


Subatomic Particles and Valence Shell

Every single object in the universe consists of basic infinitesimal particles termed atoms. Each atom has its own unique behaviors that depend on its internal foundation. They are composed of three smaller particles namely; protons, electrons, and neutrons. An element known as hydrogen is composed of a single proton but when it is added with another proton, it then becomes helium and so on.  If there is, however, a different number of neutrons inside the atomic nucleus, then it is signified as an isotope.


The Three Subatomic particles

Proton– is positively charged and weighs 1.673 x 10^-27

Electron– is negatively charged and weighs 9.11 x 10^-31

Neutron– has a neutral charge and weighs 1.675 x 10^-27

Its worth noting that protons and neutrons constitute a vast majority of the atom’s mass. While electrons are much smaller than protons and neutrons, it co-exists inside the surrounding energy orbitals. When electrons are farthest from the nucleus, they are the most reactive to certain bonds.


Conductivity, Semi-conductivity, and Insulator

Conductivity is a measurement of quantified ease when material permits electric current to flow through it. Inversely, electrical resistivity measures the contradicting force when a material resists the flow of electric current.

Relatively, a conductor is a material that gives minimal resistance to the electric current. One good example is metal due to the lesser resistance during the electron flow process.  Materials that possess high resistance are called insulators which also exhibit very low conductivity.

Between insulators and conductors are Semiconductors that have abilities in between both components. Such that when heated, semiconductors increase in conductivity while conductors experience increased resistivity.



It is the amount of charge per unit of time that passes through a specific circuit. Such that,

 I= Δq/Δt

 It is measured in Coulombs per second, or Amperes(A),

1 Ampere= 1 coulomb/second

 Current, voltage and resistance are related to each other through Ohm’s Law:


where I is current, V is voltage, and R is resistance.



It is a charged pressure that pushes electrons to move in a circuit. Voltage is a quantitative expression of electric potential difference between two charged points in an electric field. It is measured in Volts (v).

Also known as electromotive force, it is the force responsible for pushing the current through a circuit. It is somewhat similar to a difference in charged pressure due to the higher concentration of charge at one point of the components. This certain difference in concentrated charge results in a ‘voltage’.


It is a property of certain naturally insulated materials that impedes the channel of current procured by a conductor. To put it simply in perspective, conductivity and resistivity are inversely related.  Resistance is measured in Ohms.

R=⍴⋅LA, where represents the resistivity of the conductor, L is the length or distance, and A is the cross-sectional area.



It is defined as the manifestation of a phenomenon driven by electrostatic charges. More so, a magnetic field can instigate charged particles to make electricity, and there the properties of magnets are collectively known for having the potential capacity to draw electricity from the attraction and repulsion forces situated in opposite poles.

Our ASVAB Electronics Information study guide and free ASVAB electronics information practice test will help you to get 100% prepared before your big day!

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ASVAB Arithmetic Reasoning Study Guide

The ASVAB Arithmetic Reasoning test measures a candidate’s ability to solve problems representing word problems and delivers mathematical questions and equations. These may not only be simple questions involving addition, subtraction, multiplication, or division but may also require reasoning skills to determine what is really being asked for and finding the best answer.

The ASVAB Arithmetic Reasoning test measures a candidate’s ability to solve problems representing word problems and delivers mathematical questions and equations. These may not only be simple questions involving addition, subtraction, multiplication, or division but may also require reasoning skills to determine what is really being asked for and finding the best answer.


These word problems may have some technical terms, besides basic terms, such as area, perimeter, integer, or ratio, which are expected to be common mathematical knowledge. When solving Arithmetic Reasoning questions, you must pay attention not only to the numbers mentioned in the problem but also to the wording, the format of the paragraph, buzzwords, and more.


Arithmetic Reasoning Tips

Finding “buzzwords”

These words or phrases of emphasis indicate the action you will need to solve the problem. For example, if a problem mentions “difference” or “fewer” or “take away”, it may require you to use subtraction, while some words like “times” or “product” or “double” may stand for multiplication. Before solving the problems, make sure you carefully read and identify what process it requires. It will show you the direction you should take to solve the overall equation.


Identify numbers

Word problems can be simple with an addition or subtraction of 2 numbers, or they can include more complex numbers and operations. Pay your attention to all the given numbers and figures within the body of the paragraph. Read carefully these numbers, and then determine which of the numbers are relevant to solve the problem and which of them are misleading you. 

Make sure you perform them in the right order. 6 – 8 and 8 – 6 bring two very different results and may affect your pass or fail. Be as careful as possible with the number to avoid unnecessary mistakes. 


Paragraph Format

When dealing with the Arithmetic Reasoning section, you should notice that many word problems may contain irrelevant information that is used as a filler to distract you from the real question being asked. You must learn to scan all over the problem, disregard this misleading verbiage and focus on the portions that will help you answer the problem. Just because something is included in a paragraph doesn’t mean that it is important and must be used.

By identifying the format and context of the paragraph combining with the buzzwords and numbers, you can build a completed, simplified equation. Be sure that you select all necessary information, make a proper equation, and solve it. 

If you run into a problem that stumps you, skip it to move ahead to another one and then come back to it if you have time. Do not waste too much time on a problem, try to quickly solve the other questions that you are certain about it.


Steps to solving a word problem

Here is the suggested route to answer the questions in the ASVAB Arithmetic Reasoning test.

Carefully read the problem

Because of the limited time, you may push yourself to solve a problem quickly. This easily leads to a disaster of failing the test. Word problems can be tricky, so you have to thoroughly read each to identify exactly what is being asked for.

Determine the method used to answer

After thoroughly understanding the problem, you’ll need to gather all the relevant data from the problem and decide what is the best way to solve the question it is asking. 

Setup the equations

Once you have determined the method used to answer, you need to set all the relevant data into an equation that will lead you to the correct answer.

Solve equations and review results

When you have the equations for the question, solve it to find the final result. Then quickly review to make sure there is no regretful mistake in the solving progress. 

Basic Arithmetic Review

Before starting practicing the Arithmetic problems, let’s review all the basic definitions, properties, and Arithmetic Reasoning formulas you may need in the ASVAB Arithmetic.

Types of Numbers


Natural numbers (i.e. counting numbers) are numbers that are used for counting and ordering. They can be expressed mathematically as {1, 2, 3, 4, 5, …}

Even Number

Even numbers are natural numbers that are divisible by 2. 

2ℕ = { 2, 4, 6, 8, 10, 12, 14, … }

Odd Number

Odd numbers are natural numbers that are not divisible by 2. 

2ℕ + 1 = { 1, 3, 5, 7, 9, 11, 13, 15…} 

Prime Number

A prime number is a number greater than 1 that is only divisible by 1 and by itself.


2, 3, 7, and 11 are prime numbers

P = { 2, 3, 5, 7, 11, 13, 17, 19,…}

Composite Number

Composite numbers are the product of some prime numbers. For example:

8 = 2 ⋅ 2⋅ 2

10 = 2 ⋅ 5


In mathematics, the whole numbers are the basic counting numbers 0, 1, 2, 3, 4, 5, 6, … and so on.


An integer number includes all positive whole numbers (a positive integer), and negative whole numbers (a negative integer), or zero.

asvab arithmetic reasoning

We can put that all together like this:

Integers = { …, −4, −3, −2, −1, 0, 1, 2, 3, 4, … }


Fraction/rational number is a ratio of two integer numbers in the form of A/B, where A and B are integers and B#0.

A is called Numerator

B is called Denominator


Real numbers that cannot be written as the quotient of two

integers but can be represented on the number line.


-2√3 , √2, π


Include all numbers that can be represented on the number

line, that is, all rational and irrational numbers.

The Basic Number Properties

Four basic properties of numbers include commutative, associative, distributive, and identity. You should familiarize yourself with each of these before taking the Arithmetic Reasoning subtest.


Properties of addition

Identity Property of Zero

a + 0 = a

Inverse Property

a + (-a) = 0 

Commutative Property

When adding two numbers together, the outcome (sum) is the same regardless of the order the numbers are placed in.

a + b = b + a

For example, the two following equations end up with the same result:

4 + 6 = 10 or 6 + 4 = 10

Associative Property

When adding multiple numbers together, the outcome (sum) is the same regardless of the order the numbers are placed in.

(a + b) + c = a + (b + c) 


Properties of subtractions


Unlike addition, the order of two numbers in subtraction changes all the results. In other words, the subtrahend and minuend are distinct factors when subtracting and they cannot be switched order-wise (except subtrahend and minuend are equal).

a – b # b – a

For example :

8 – 6 = 2 is not the same as 6 – 8 = -2


When subtracting multiple numbers, the order of the numbers does matter. Subtracting numbers in different orders will result in different outcomes. 


Properties of multiplication

  • Property of Zero

a × 0 = a

  • Identity Property of One

a × 1 = a, where a # 0

  • Inverse Property

a × 1/a  = 1, where a # 0

  • Commutative Property

When multiplying two numbers together, the product is the same regardless of the order the numbers are placed in.

a × b = b × a

For example, the two following equations end up with the same result:

2 × 3 = 6 or 3 × 2 = 6

Associative Property :

When multiplying multiple numbers together, the product is the same regardless of the order the numbers are placed in.

(a × b) × c = a × (b × c)

For example :

(2 × 3) × 4 = 2 × (3 × 4) = 24


Properties of division

Property of Zero

0/a = 0, when a # 0.

Property of One

a/a = 1 when a # 0

Identity Property of One

a/1 = a × 1.

Absolute Value

The absolute value of a number is always greater than 0. 

If a > 0, |a| = a. 

If a < 0, |a| = a. 

For example, |8| = 8 and |-8| = 8. In each case, the answer is positive.

Order of Operations 

Step 1 : Parentheses – Simplify any expressions inside parentheses. 

Step 2 : Exponents (Powers, Roots) – Work out any exponents. 

Step 3 : Multiply or Divide before you Add or Subtract

Step 4 : Addition and Subtraction These are done last, working from left to right.

For example:

10 – 8 × 4 + (6 ÷ 3) + 5 × 23 

= 10 – 8 × 4 + 2 + 5 × 8

= 10 – 32 + 2 + 40

= 20

>> More: General Science ASVAB Study Guide


Adding and subtracting with negatives

– a – b = (-a) + (-b)

– a + b = b – a

a – (-b) = a + b 


– 2 – 3 = (-2) + (-3) = -5

– 2 + 5 = 5 – 2 = 3

2 – (-3) = 2 + 3 = 5


Multiplying and dividing with negatives

-a × b = -ab

-a × -b = ab

(-a)/(-b) = a/b, b # 0

(-a)/b = -a/b, b # 0


-2 × 3 = -6

-2 × -3 = 6

(-2)/(-3) = ⅔

(-2)/3 = -⅔



Fractions are another way to express division. The top number of a fraction is called the numerator, and the bottom number is called the denominator.

Least common multiple

The LCM of a set of numbers is the smallest number that is a multiple of all the given numbers. For example, the LCM of 5 and 6 is 30, since 5 and 6 have no factors in common. 

Greatest common factor

The GCF of a set of numbers is the largest number that can be evenly divided into each of the given numbers. For example, the GCF of 24 and 27 is 3, since both 24 and 27 are divisible by 3, but they are not both divisible by any numbers larger than 3. 

Adding and subtracting fractions

Fractions must have the same denominator before they can be added or subtracted.

asvab arithmetic reasoning 2

If the fractions have different denominators, rewrite them as equivalent fractions with a common denominator. Then add or subtract the numerators, keeping the denominators the same. For example :

asvab arithmetic reasoningarithmetic reasoning formula


Multiplying and dividing fractions

When multiplying and dividing fractions, a common denominator is not needed. To multiply, take the product of the numerators and the product of the denominators :

asvab arithmetic study guide

Example :

⅔ × ⅛ = (2 × 1 )/(3 × 8) = 2/24 = 1/12

To divide fractions, invert the second fraction and then multiply the numerators and denominators :

arithmetic reasoning

⅔ ÷ ⅛ = (2 × 8)/(3 × 1) = 16/3.


Hope that all these study guides about arithmetic reasoning ASVAB help you prepare well for your coming exam! Take our free ASVAB Arithmetic Reasoning practice test now to practice all you have learned!

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ASVAB General Science Study Guide 1

The ASVAB General Science subtest is designed to test your scientific knowledge. Let's read our lessons and tips for the Science section of the ASVAB to get 100% ready for your coming ASVAB.

The ASVAB General Science subtest is designed to test your scientific knowledge. The subtest is NOT a part of your Armed Forces Qualification Test score. However, if you desire a job field that is related to science, you will need to perform your best on the general science test to qualify for that job.

Because it is a general science test, students must show their general knowledge of a variety of scientific areas, including Earth & Space Science, Life Science, and Physical Science. Each portion of the general test has the same role, make sure you do not focus too heavily on any one area. 

Part 1 of our Free General Science ASVAB Study Guide covers the general information you need to know about Earth & Space Science. This topic will show all the knowledge about the structure of the Earth, Plate tectonics, Types of rocks, Water cycle, Earth’s Atmosphere, Planets, and Comets.

Earth & Space Science

Structure of the Earth

asvab general science

The Earth is consists of three main layers:

The outer silicate solid crust is the rocky outer layer of the Earth. It is very thin (5–70 kilometers in depth) compared to the other two layers.

The Earth’s mantle is the planet’s thickest layer with a depth of 2,890 km. It is a hot, solid rock layer located under the crust.

The core is a large sphere of metal that forms the center of the Earth. It concludes a liquid outer core whose flow produces the Earth’s magnetic field and a solid inner core.

Plates tectonics

Plate tectonics is the theory that Earth’s outermost layer is divided into large slabs of solid rock, called “plates,” that drift slowly. They move at about 1/2 to 4 inches (1.3 to 10 centimeters) per year.

There are two types of plates – oceanic plates and continental plates. As these plates move, the continents glide slowly. Based on the direction of a plate’s movement as well as its relationship to the beside plates, various different boundaries may be formed:

Divergent plate boundaries occur when 2 tectonic plates move away from each other. Here, earthquakes happen commonly and magma (molten rock) from the mantle rises to the surface and creates a new oceanic crust. 

Convergent plate boundaries form when two plates come together and collide. The impact of the colliding plates causes the edges of the plates to buckle up then creating mountain ranges or one of the plates may bend down into a deep seafloor trench.

Transform fault boundaries 

A transform fault or transform boundary occurs when plates move sideways past each other horizontally. It ends suddenly when it connects to another plate boundary, or another transform, a spreading ridge, or a subduction zone.

Types of rocks

In your ASVAB General Science section, you may be asked about the types of rocks as well as their properties. Let’s take a look to obtain this information.

Igneous rock, sedimentary rock, and metamorphic rock are the three main types of rocks.

Igneous rock is formed when magma or lava from inside the earth cools and solidifies. This type of rock majorly makes up the Earth’s crust (ex: basalt, obsidian, and granite).

Sedimentary rock is formed over time when smaller sediments and inorganic material are layered, squeezed, and solidified. (ex: sandstone, limestone, coal, and shale).

Metamorphic rock forms when igneous or sedimentary rock is transformed by heat, pressure, or chemical reactions. (ex: slate, marble, and quartzite).

Water cycle

There is some facts about the water you may need while doing your ASVAB General Science subtest:

Water occupies 71% of Earth’s surface in the oceans, lakes, rivers, and glaciers.

On the Fahrenheit temperature scale, water freezes at 32° and boils at 212°. On the Celsius scale, water freezes at 0°C and boils at 100°C.

Saltwater makes up 97% of the water on Earth. Of 3% of remaining freshwater, and two-thirds of it is ice.

Earth’s liquid freshwater is mainly in the form of groundwater.

asvab general science study guide

The water cycle describes the continuous movement of water to the atmosphere by evaporation and then from the atmosphere to the land by precipitation.

Evaporation: Heats of the sun change water on the Earth’s surface from liquid to gas state. This vapor can then rise up into the atmosphere. Water also evaporates from plants, in a process called transpiration.

Condensation: Water vapor rises into the sky, turning back into a liquid, then forming clouds.

Precipitation is any product of the condensation of water vapor in the atmosphere that falls from clouds. This includes rain, snow, and hail.

Earth’s Atmosphere

This information will help you improve your knowledge about the atmosphere of the Earth and easily solve this kind of question in your ASVAB General Science test.

Earth’s atmosphere is made up of 78% nitrogen, 21% oxygen, 0.9% argon, and 0.1 percent other gases (carbon dioxide, methane, water vapor, and neon).

Layers of the Atmosphere: From lowest to highest, the five main layers are:

Troposphere: This is the lowest layer of the atmosphere where we live in. Weather almost takes place in this layer. In this layer, the higher the distance above the earth is, the colder the temperature gets (by about 6.5°C per kilometer).

Stratosphere: This extends upwards of about 50 km from the troposphere. It contains the Ozone layer. In this zone, due to the absorption of ultraviolet (UV) radiation from the sun by the Ozone layer, temperature increases with height.

The Mesosphere is located above the stratosphere. The temperature here also decreases with height, with the minimum of about -90°C at the “mesopause”.

Thermosphere: The International Space Station orbits lie in this layer. The thermosphere is above the mesopause. In this region, the temperatures again increase with height. This may be caused by the absorption of energetic ultraviolet and X-Ray radiation from the sun.

Exosphere:  The region higher than 500 km is called the exosphere. This region contains mainly oxygen and hydrogen atoms. Most of the satellites orbiting Earth are in here.

The planets

asvab general science study guide

Planet Facts:

The planets can be divided into 2 groups. The first group concluding inner planets that are small, dense, and rocky (Mercury, Venus, Earth, and Mars). Another one consists of 4 planets called the terrestrial planets because of their solid planetary surfaces.

Here are the 8 planets listed in order of nearest distance to the Sun:

Mercury: The smallest of the terrestrial planets in the solar system and the closest to the sun. It is only slightly bigger than the Earth’s Moon. It is also the fastest planet,  taking 88 Earth days to zip one revolution around the sun.

Venus: The brightest object in our night sky following the moon. Venus spins slowly in the opposite direction from most planets. The rate of its rotation is very slow. Venus takes 243 days to rotate around its axis, which is even longer than it takes to complete a revolution around the sun. A very thick atmosphere composed of carbon dioxide and droplets of sulfuric acid traps heat making it the hottest planet.

Earth: Unique from the other planets because it is the only place we know of so far existing living things. Its surface has a suitable condition of atmosphere and temperature for the existence of liquid water to support life.

Mars: A “red planet” with a dusty, cold, desert surface and very thin atmosphere. There is evidence that Mars had a great deal of liquid surface water billions of years ago.

Jupiter: The largest planet in our solar system and more than twice as massive as all other planets in the system combined. It is also the planet with the biggest number of the moon with I79 in total. Jupiter contains major hydrogen and helium. 

Saturn: The second-largest planet in our solar system with a spectacular dazzling, complex system of icy rings. Saturn has 62 moons. 

Uranus: The seventh planet from the Sun – its most unusual characteristic is that the axis is tilted more than 90°. This unique tilt makes Uranus seem to spin on its side.

Neptune: The farthest planet from the Sun – has a bluish color due to the methane in its atmosphere. It is a dark, cold planet and whipped by supersonic winds.


Comets are cosmic snowballs made up of frozen gases, rocks, and dust that orbit the Sun. People are sometimes called Comets “dirty snowballs”. When a comet’s orbit takes it close to the Sun, it begins to heat up and release gases and dust in the outgassing process. This creates a giant glowing head larger than many planets. The dust and gas tail can stretch for millions of miles. 

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