Gwen had
25 as much money as Betty. Gwen had $42 less than Betty. Gwen spent some money to buy a birthday present for her cousin. In the end, she had
110 as much money as Betty. How much did Gwen spend on the birthday present?
|
Gwen |
Betty |
Before |
2 u |
5 u |
Change |
- ? |
|
After |
1 p |
10 p |
Amount that Gwen had less than Betty
= 5 u - 2 u
= 3 u
3 u = 42
1 u = 42 ÷ 3 = 14
Amount that Gwen had at first
= 2 u
= 2 x 14
= $28
Amount that Betty had
= 5 u
= 5 x 14
= $70
The amount that Betty had at first and in the end remains the same.
5 u = 10 p
10 p = 70
1 p = 70 ÷ 10 = 7
Amount that Gwen had in the end
= 1 p
= $7
Amount that Gwen spent on the birthday present
= 28 - 7
= $21
Answer(s): $21