Gwen's uncle is 4 times as old as her. Gwen will be 16 years old in 6 years' time. In how many years' time will Gwen's age be 60% that of her uncle's?
| |
Gwen's uncle |
Gwen |
Difference |
Before
(now) |
4x2 =
8 u |
1x2 =
2 u |
3x2 =
6 u |
| Change 1 |
+ 6 |
+ 6 |
|
| After 1 |
|
16 |
|
| Change 2 |
+ ? |
+ ? |
|
| After 2 |
5x3 =
15 u |
3x3 =
9 u |
2x3 =
6 u |
60% =
60100 =
35 Gwen's uncle : Gwen = 5 : 3
The difference in age between Gwen's uncle and Gwen always remains the same. Make the difference in age between Gwen's uncle and Gwen the same. LCM of 3 and 2 is 6.
2 u + 6 = 16
2 u = 16 - 6
2 u = 10
1 u = 10 ÷ 2 = 5
Number of years' time when Gwen's age will be 60% that of her uncle's
= 15 u - 46
= 15 x 5 - 46
= 75 - 46
= 29
Answer(s): 29
