Cathy had
38 as much money as Joelle. Cathy had $50 less than Joelle. Cathy spent some money to buy a birthday present for her uncle. In the end, she had
110 as much money as Joelle. How much did Cathy spend on the birthday present?
|
Cathy |
Joelle |
Before |
3 u |
8 u |
Change |
- ? |
|
After |
1 p |
10 p |
Amount that Cathy had less than Joelle
= 8 u - 3 u
= 5 u
5 u = 50
1 u = 50 ÷ 5 = 10
Amount that Cathy had at first
= 3 u
= 3 x 10
= $30
Amount that Joelle had
= 8 u
= 8 x 10
= $80
The amount that Joelle had at first and in the end remains the same.
8 u = 10 p
10 p = 80
1 p = 80 ÷ 10 = 8
Amount that Cathy had in the end
= 1 p
= $8
Amount that Cathy spent on the birthday present
= 30 - 8
= $22
Answer(s): $22