Yoko and Ivory have some money. If Yoko spends $25, she will have
25 as much money as Ivory. If Ivory spends $23, Yoko will have
78 as much money as Ivory. How much money does Ivory have?
| |
Case 1 |
Case 2 |
| |
Yoko |
Ivory |
Yoko |
Ivory |
| Before |
2 u + $25 |
5 u |
7 p |
8 p + $23 |
| Change |
- $25 |
|
|
- $23 |
| After |
2 u |
5 u |
7 p |
8 p |
The amount that Yoko has at first in Case 1 and Case 2 is the same.
2 u + 25 = 7 p
2 u = 7 p - 25 --- (1)
The amount that Ivory has at first in Case 1 and Case 2 is the same.
5 u = 8 p + 23 --- (2)
Make u the same.
(1)
x 510 u = 35 p - 125 --- (3)
(2)
x 210 u = 16 p + 46 --- (4)
(3) = (4)
35 p - 125 = 16 p + 46
35 p - 16 p = 125 + 46
19 p = 171
1 p = 171 ÷ 19 = 9
Amount that Ivory has
= 8 p + 23
= 8 x 9 + 23
= 72 + 23
= $95
Answer(s): $95
