Zara and Fiona had $154. Fiona had $40 more than Zara. Zara spent 3 times as much as Fiona and was left with
25 as much as Fiona. How much did Zara spend more than Fiona?
| |
Make p the same
(1)x5 = (3) |
Zara
(1) |
Fiona
(2) |
Make p the same
(2)x2 = (4) |
Total
|
Comparing Zara
and Fiona at first |
|
|
$40 more |
|
$154 |
| Before |
$285 |
$57 |
$97 |
$194 |
|
| Change |
- 15 u |
- 3 u |
- 1 u |
- 2 u |
|
| After |
10 p |
2 p |
5 p |
10 p |
|
Amount that Zara had at first
= (154 - 40) ÷ 2
= 114 ÷ 2
= $57
Amount that Fiona had at first
= 57 + 40
= $97
57 - 3 u = 2 p --- (1)
97 - 1 u = 5 p --- (2)
Make p the same.
(1)
x 5
285 - 15 u =
10 p --- (3)
(2)
x 2
194 - 2 u =
10 p --- (4)
(4) = (3)
194 - 2 u = 285 - 15 u
15 u - 2 u = 285 - 194
13 u = 91
1 u = 91 ÷ 13 = 7
Amount that Zara spent more than Fiona
= 3 u - 1 u
= 2 u
= 2 x 7
= $14
Answer(s): $14
