Cindy and Nicole have some money. If Cindy spends $23, she will have
25 as much money as Nicole. If Nicole spends $28, Cindy will have
78 as much money as Nicole. How much money does Cindy have?
| |
Case 1 |
Case 2 |
| |
Cindy |
Nicole |
Cindy |
Nicole |
| Before |
2 u + $23 |
5 u |
7 p |
8 p + $28 |
| Change |
- $23 |
|
|
- $28 |
| After |
2 u |
5 u |
7 p |
8 p |
The amount that Cindy has at first in Case 1 and Case 2 is the same.
2 u + 23 = 7 p
2 u = 7 p - 23 --- (1)
The amount that Nicole has at first in Case 1 and Case 2 is the same.
5 u = 8 p + 28 --- (2)
Make u the same.
(1)
x 510 u = 35 p - 115 --- (3)
(2)
x 210 u = 16 p + 56 --- (4)
(3) = (4)
35 p - 115 = 16 p + 56
35 p - 16 p = 115 + 56
19 p = 171
1 p = 171 ÷ 19 = 9
Amount that Cindy has
= 7 p
= 7 x 9
= $63
Answer(s): $63
