Oscar is 3 times as old as his brother. In 12 years' time, Oscar will be 10 years less than twice of his brother's age. How old will Oscar be in 6 years' time?
|
Oscar |
Oscar's brother |
Difference |
Before |
3 u |
1 u |
2 u |
Change |
+ 12 |
+ 12 |
|
After |
2 p - 10 |
1 p |
1 p - 10 |
Difference in their ages at first
= 3 u - 1 u
= 2 u
Difference in their ages in the end
= 2 p - 10 - 1 p
= 1 p - 10
The difference in their ages remains unchanged.
2 u = 1 p - 10
2 u + 10 =
1 p --- (1)
Age of Oscar's brother in 12 years' time
= 1 u + 12
1 u + 12 =
1 p --- (2)
(1) = (2)
2 u + 10 = 1 u + 12
2 u - 1 u = 12 - 10
1 u = 2
Oscar's current age
= 3 u
= 3 x 2
= 6
Oscar's age in 6 years' time
= 6 + 6
= 12
Answer(s): 12