Pamela and Ivory have some money. If Pamela spends $10, she will have
25 as much money as Ivory. If Ivory spends $2, Pamela will have
47 as much money as Ivory. How much money does Ivory have?
| |
Case 1 |
Case 2 |
| |
Pamela |
Ivory |
Pamela |
Ivory |
| Before |
2 u + $10 |
5 u |
4 p |
7 p + $2 |
| Change |
- $10 |
|
|
- $2 |
| After |
2 u |
5 u |
4 p |
7 p |
The amount that Pamela has at first in Case 1 and Case 2 is the same.
2 u + 10 = 4 p
2 u = 4 p - 10 --- (1)
The amount that Ivory has at first in Case 1 and Case 2 is the same.
5 u = 7 p + 2 --- (2)
Make u the same.
(1)
x 510 u = 20 p - 50 --- (3)
(2)
x 210 u = 14 p + 4 --- (4)
(3) = (4)
20 p - 50 = 14 p + 4
20 p - 14 p = 50 + 4
6 p = 54
1 p = 54 ÷ 6 = 9
Amount that Ivory has
= 7 p + 2
= 7 x 9 + 2
= 63 + 2
= $65
Answer(s): $65
