Jane and Zara had $131. Zara had $19 more than Jane. Jane spent 3 times as much as Zara and was left with
25 as much as Zara. How much did Zara spend less than Jane?
| |
Make p the same
(1) x 5 = (3) |
Jane
(1) |
Zara
(2) |
Make p the same
(2) x 2 = (4) |
Total
|
Comparing Jane
and Zara at first |
|
|
$19 more |
|
$131 |
| Before |
$280 |
$56 |
$75 |
$150 |
|
| Change |
- 15 u |
- 3 u |
- 1 u |
- 2 u |
|
| After |
10 p |
2 p |
5 p |
10 p |
|
Amount that Jane had at first
= (131 - 19) ÷ 2
= 112 ÷ 2
= $56
Amount that Zara had at first
= 56 + 19
= $75
56 - 3 u = 2 p --- (1)
75 - 1 u = 5 p --- (2)
Make p the same.
(1)
x 5
280 - 15 u =
10 p --- (3)
(2)
x 2
150 - 2 u =
10 p --- (4)
(4) = (3)
150 - 2 u = 280 - 15 u
15 u - 2 u = 280 - 150
13 u = 130
1 u = 130 ÷ 13 = 10
Amount that Zara spent less than Jane
= 3 u - 1 u
= 2 u
= 2 x 10
= $20
Answer(s): $20
