Oscar's age is
13 of his granduncle's. His granduncle will be 64 years old in 19 years' time. In how many years' time will Oscar's age be
23 that of his granduncle's?
| |
Oscar |
His granduncle |
Difference |
| Before |
1x1 =
1 u |
3x1 =
3 u |
2x1 =
2 u |
| Change 1 |
+ 19 |
+ 19 |
|
| After |
|
64 |
|
| Change 2 |
+ ? |
+ ? |
|
| After 2 |
2x2 =
4 u |
3x2 =
6 u |
1x2 =
2 u |
The age difference between Oscar and his granduncle remains unchanged.
LCM of 2 and 1 is 2.
3 u + 19 = 64
3 u = 64 - 19
3 u = 45
1 u = 45 ÷ 3 = 15
Number of years' time when Oscar's age will be
23 that of his granduncle's age
= 4 u - 1 u
= 3 u
= 3 x 15
= 45
Answer(s): 45
