Question

A sales associate in a department store earns a commission on each suit and each pair of shoes sold. One week, she earned $47 in commission for selling 3 suits and a pair of shoes. The next week, she earned $107 in commission for selling 7 suits and 2 pairs of shoes. How much commission does she earn for selling each suit and each pair of shoes? Solve by substitution.

Answer 1

Let h shoes and s suit:

3s+h=47

7s+2h=107

substitution property:

3s=47-h

s=(47-h)/3

plug it into the other equation and solve for h:


7((47-h)/3)+2h=107

distribute 7 and multiply 3 on both sides:

329-7h+6h = 321

329-h=321

-h=-8

h=8 pair of shoes

s=(47-8)/3=13 suits