Ryan's uncle is 5 times as old as him. His uncle will be 53 years old in 8 years' time. In how many years' time will Ryan's age be 60% that of his uncle's?
| |
Ryan's uncle |
Ryan |
Difference |
Before
(now) |
5x1 =
5 u |
1x1 =
1 u |
4x1 =
4 u |
| Change 1 |
+ 8 |
+ 8 |
|
| After 1 |
53 |
|
|
| Change 2 |
+ ? |
+ ? |
|
| After 2 |
5x2 =
10 u |
3x2 =
6 u |
2x2 =
4 u |
60% =
60100 =
35 Ryan's uncle : Ryan = 5 : 3
The difference in age between Ryan's uncle and Ryan always remains the same. Make the difference in age between Ryan's uncle and Ryan the same. LCM of 4 and 2 is 4.
5 u + 8 = 53
5 u = 53 - 8
5 u = 45
1 u = 45 ÷ 5 = 9
Number of years' time when Ryan's age will be 60% that of his uncle's
= 10 u - 53
= 10 x 9 - 53
= 90 - 53
= 37
Answer(s): 37
