The ratio of David's money to Vincent's money is 7 : 13. If Vincent has $312, how much must he give to David so both will have the equal amount of money?
| |
David |
Vincent |
Total |
| Before |
7 u |
13 u |
20 u |
| Change |
+ 3 u |
- 3 u |
|
| After |
10 u |
10 u |
20 u |
Comparing David and
Vincent in the end |
1 |
1 |
|
Amount that Vincent has at first = 13 u
13 u = 312
1 u = 312 ÷ 13 = 24
Total amount that Vincent and David have
= 7 u + 13 u
= 20 u
Amount that each of them will have in the end
= 20 u ÷ 2
= 10 u
Amount that Vincent must give to David
= 10 u - 7 u
= 3 u
= 3 x 24
= $72
Answer(s): $72
