Shiyun and Abi had $80. Abi had $8 more than Shiyun. Shiyun spent 2 times as much as Abi and was left with
23 as much as Abi. How much did Shiyun spend?
| |
Make p the same
(1)x3 = (3) |
Shiyun
(1) |
Abi
(2) |
Make p the same
(2)x2 = (4) |
Total
|
Comparing Shiyun
and Abi at first |
|
|
$8 more |
|
$80 |
| Before |
$108 |
$36 |
$44 |
$88 |
|
| Change |
- 6 u |
- 2 u |
- 1 u |
- 2 u |
|
| After |
6 p |
2 p |
3 p |
6 p |
|
Amount that Shiyun had at first
= (80 - 8) ÷ 2
= 72 ÷ 2
= $36
Amount that Abi had at first
= 36 + 8
= $44
36 - 2 u = 2 p --- (1)
44 - 1 u = 3 p --- (2)
Make p the same.
(1)
x 3
108 - 6 u =
6 p --- (3)
(2)
x 2
88 - 2 u =
6 p --- (4)
(4) = (3)
88 - 2 u = 108 - 6 u
6 u - 2 u = 108 - 88
4 u = 20
1 u = 20 ÷ 4 = 5
Amount that Shiyun spent
= 2 u
= 2 x 5
= $10
Answer(s): $10
