Cindy had
49 as much money as Shiyun. Cindy had $50 less than Shiyun. Cindy spent some money to buy a birthday present for her buddy. In the end, she had
13 as much money as Shiyun. How much did Cindy spend on the birthday present?
| |
Cindy |
Shiyun |
| Before |
4 u |
9 u |
| Change |
- ? |
|
| After |
1 p |
3 p |
Amount that Cindy had less than Shiyun
= 9 u - 4 u
= 5 u
5 u = 50
1 u = 50 ÷ 5 = 10
Amount that Cindy had at first
= 4 u
= 4 x 10
= $40
Amount that Shiyun had
= 9 u
= 9 x 10
= $90
The amount that Shiyun had at first and in the end remains the same.
9 u = 3 p
3 p = 90
1 p = 90 ÷ 3 = 30
Amount that Cindy had in the end
= 1 p
= $30
Amount that Cindy spent on the birthday present
= 40 - 30
= $10
Answer(s): $10
