Question

One day a store sold 28 sweatshirts. White ones cost $9.95 and yellow ones cost $13.50. In all, $321.20 worth of sweatshirts were sold. How many of each color were sold?

Answer 1

white sold = 16

yellow sold = 12

Explanation:

w = # of white sold

y = # of yellow sold

w + y = 28 solve this for w

w = 28 - y

9.95w + 13.5y = 321.20 substitute w = 28-y into this expression and solve for y

9.95(28-y) + 13.5y = 321.20

278.60 - 9.95y + 13.50y = 321.20

278.60 + 3.55y = 321.20

3.55y = 321.20 - 278.60 = 42.60

y = 42.60/3.55 = 12 substitute this into w = 28 - y and solve for w

w = 28 - 12 = 16