Gem's uncle is 4 times as old as her. Gem will be 14 years old in 4 years' time. In how many years' time will Gem's age be 60% that of her uncle's?
| |
Gem's uncle |
Gem |
Difference |
Before
(now) |
4x2 =
8 u |
1x2 =
2 u |
3x2 =
6 u |
| Change 1 |
+ 4 |
+ 4 |
|
| After 1 |
|
14 |
|
| Change 2 |
+ ? |
+ ? |
|
| After 2 |
5x3 =
15 u |
3x3 =
9 u |
2x3 =
6 u |
60% =
60100 =
35 Gem's uncle : Gem = 5 : 3
The difference in age between Gem's uncle and Gem always remains the same. Make the difference in age between Gem's uncle and Gem the same. LCM of 3 and 2 is 6.
2 u + 4 = 14
2 u = 14 - 4
2 u = 10
1 u = 10 ÷ 2 = 5
Number of years' time when Gem's age will be 60% that of her uncle's
= 15 u - 44
= 15 x 5 - 44
= 75 - 44
= 31
Answer(s): 31
