Question

A sports store sell soccer balls and basketballs. Last month they sold 21 balls for a total of $190. If a soccer ball costs $8 and a basketball costs $10, how many soccer balls were sold?​

Answer 1

Let s = soccer balls and b = basketballs

s + b = 21
8s + 10b = 190

b=21 - s

8s + 10(21 - s) = 190
8s + 210 - 10s = 190
210 - 2s = 190
-2s = -20
s = 10

10 soccer balls were sold