45 Irene's money was equal to
25 of Xuan's money at first. After Irene spent $2.10 and Xuan spent $1.10, Irene had
25 as much money as Xuan.
- How much did Xuan have at first? Express your answer in 2 decimal places.
- How much did Irene have in the end? Express your answer in 2 decimal places.
| |
Make p the same
(3)x5 |
Irene
(1) |
Xuan
(2) |
Make p the same
(4)x2 |
| Before |
25 u |
5 u |
10 u |
20 u |
| Change |
- 10.5 |
- 2.1 |
- 1.1 |
- 2.2 |
| After |
10 p |
2 p |
5p |
10 p |
45 Irene's money =
25 Xuan's money
45 Irene's money =
410 Xuan's money
Irene's money : Xuan's money = 5 : 10
(3) = (4)
25 u - 10.5 = 20 u - 2.2
25 u - 20 u = 10.5 - 2.2
5 u = 8.3
1 u = 1.66
Amount Xuan has at first
= 10 u
= 10 x 1.66
= 16.6 (a)
Amount Irene has in the end
= 5 u - 2.1
= (5 x 1.66) - 2.1
= 6.2 (b)
Answers: (a) $16.60; (b) $6.20
