Xandra and Anna had $168. Anna had $24 more than Xandra. Xandra spent 3 times as much as Anna and was left with
35 as much as Anna. How much did Xandra spend?
| |
Make p the same
(1)x5 = (3) |
Xandra
(1) |
Anna
(2) |
Make p the same
(2)x3 = (4) |
Total
|
Comparing Xandra
and Anna at first |
|
|
$24 more |
|
$168 |
| Before |
$360 |
$72 |
$96 |
$288 |
|
| Change |
- 15 u |
- 3 u |
- 1 u |
- 3 u |
|
| After |
15 p |
3 p |
5 p |
15 p |
|
Amount that Xandra had at first
= (168 - 24) ÷ 2
= 144 ÷ 2
= $72
Amount that Anna had at first
= 72 + 24
= $96
72 - 3 u = 3 p --- (1)
96 - 1 u = 5 p --- (2)
Make p the same.
(1)
x 5
360 - 15 u =
15 p --- (3)
(2)
x 3
288 - 3 u =
15 p --- (4)
(4) = (3)
288 - 3 u = 360 - 15 u
15 u - 3 u = 360 - 288
12 u = 72
1 u = 72 ÷ 12 = 6
Amount that Xandra spent
= 3 u
= 3 x 6
= $18
Answer(s): $18
