How many footballs, basketballs and volleyballs were sold?

Question

a store sells footballs, basketballs, and volleyballs.  Football costs $35, Basketball costs $25 and volleyballs $15.  One day the store sold 5 times as many footballs as volleyballs.  They brought in a total of $3750 that day and the money made from basketballs alone was 4 times the money made from volleyballs alone.  How many footballs, basketballs and volleyballs did they sell.

Answer 1

Let v=number of volleyballs. Cost of v volleyballs=$15v.

Number of footballs=5v. Cost of 5v footballs=5×35v=$175v.

Cost of basketballs=4×15v=$60v. Number of basketballs=60v/25=12v/5.

So total cost=15v+175v+60v=3750, 250v=3750, v, the number of volleyballs,=15.

Number of footballs=5×15=75. Number of basketballs=(12/5)v=12×15/5=36.

Total number sold=15+75+36=126 balls.

CHECK

15×15+36×25+75×35=3750, total cost OK.

Number of footballs=5×number of volleyballs=5×15=75, OK.

Sales from basketballs=36×25=$900, sales from volleyballs=15×15=$225, so sales from basketballs is 4×225=$900, OK.