The ratio of Harry's money to Riordan's money is 7 : 13. If Riordan has $117, how much must he give to Harry so both will have the equal amount of money?
| |
Harry |
Riordan |
Total |
| Before |
7 u |
13 u |
20 u |
| Change |
+ 3 u |
- 3 u |
|
| After |
10 u |
10 u |
20 u |
Comparing Harry and
Riordan in the end |
1 |
1 |
|
Amount that Riordan has at first = 13 u
13 u = 117
1 u = 117 ÷ 13 = 9
Total amount that Riordan and Harry have
= 7 u + 13 u
= 20 u
Amount that each of them will have in the end
= 20 u ÷ 2
= 10 u
Amount that Riordan must give to Harry
= 10 u - 7 u
= 3 u
= 3 x 9
= $27
Answer(s): $27
