At Michael's smoothie shop smoothies cost $3.50 during the week and $4.00 on weekends. If Jonathan bought a smoothie every day except Saturday how much did he spend on smoothies that week?
Compute the total amount paid for smoothies bought from Monday to Friday (5 days) at $3.50/smoothie:
5 x $3.50 = $17.50
Add this to the amount paid for the smoothie bought on Sunday at $4.00/smoothie:
$17.50 + $4.00 = $21.50