Zara had $400 less than David. David spent 0.9 of his money and Zara spent 0.4 of her money. In the end, David and Zara had the same amount of money left. Find the amount of money Zara had at first.
| |
Zara |
David |
Difference |
| Before |
5 u |
30 u |
25 u |
| Change |
- 1 u |
- 3 u |
|
| After |
3 u |
3 u |
|
0.9 =
910 Fraction of David's amount left
= 1 -
910 =
110 0.4 =
25 Fraction of Zara's amount left
= 1 -
25 =
35 The amount that David and Zara each had in the end is the same. Make the numerators the same. LCM of 1 and 3 is 3.
110 of David's amount =
35 of Zara's amount
330 of David's amount =
35 of Zara's amount
Amount that Zara had less than David
= 30 u - 5 u
= 25 u
25 u = 400
1 u = 400 ÷ 25 = 16
Amount that Zara had at first
= 5 u
= 5 x 16
= $80
Answer(s): $80
