Irene and Tammy had $101. Tammy had $1 more than Irene. Irene spent 2 times as much as Tammy and was left with
23 as much as Tammy. How much did Irene spend?
| |
Make p the same
(1)x3 = (3) |
Irene
(1) |
Tammy
(2) |
Make p the same
(2)x2 = (4) |
Total
|
Comparing Irene
and Tammy at first |
|
|
$1 more |
|
$101 |
| Before |
$150 |
$50 |
$51 |
$102 |
|
| Change |
- 6 u |
- 2 u |
- 1 u |
- 2 u |
|
| After |
6 p |
2 p |
3 p |
6 p |
|
Amount that Irene had at first
= (101 - 1) ÷ 2
= 100 ÷ 2
= $50
Amount that Tammy had at first
= 50 + 1
= $51
50 - 2 u = 2 p --- (1)
51 - 1 u = 3 p --- (2)
Make p the same.
(1)
x 3
150 - 6 u =
6 p --- (3)
(2)
x 2
102 - 2 u =
6 p --- (4)
(4) = (3)
102 - 2 u = 150 - 6 u
6 u - 2 u = 150 - 102
4 u = 48
1 u = 48 ÷ 4 = 12
Amount that Irene spent
= 2 u
= 2 x 12
= $24
Answer(s): $24
