How to solve a word problem

Question

One day a store sold 31 sweatshirts. White ones cost $10.9510.95 and yellow ones cost $11.50. In all, $349.90 worth of sweatshirts were sold. How many of each color were sold?

Answer 1

Hi Karina;

 

Choose variables to represent the unknowns and set up equations from information given.

 

w = # white tee shirts

y = # yellow tee shirts

 

w + y = 31

10.95w + 11.5y = 349.9

 

Solve for w in terms of y in 1st equation and substitute into 2nd equation:

w = 31-y

10.95(31-y) + 11.5y = 349.9

339.45 - 10.95y + 11.5y = 349.9

.055y = 349.9 - 339.45

0.55y = 10.45

y = 19 yellow tee shirts sold

 

w + y = 31

w + 19 = 31

w = 12 white tee shirts sold

 

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