Question

A woman bought some large frames for $19 each and some small frames for $9 each at a closeout sale. If she bought

11 frames for $129, find how many of each type she bought.

Answer 1

She bought 3 large frames and 8 small frames.

Explanation:

X= Large frames = $19

Y= Small frames = $ 9

Total Frames Cost = $129

Total Frames = 11

Then, costs formula:

1) 19X + 9Y = 129

2) X + Y = 11

So here you have a equation system and we will solve it by substituion method:

2) Y = 11-X

replace Y in 1)

1) 19X + 9(11-X) = 129

19X +99 -9X = 129

10X = 129-99

10X = 30

X = 30/10

X = 3

Then

Y = 11-3

Y = 8