The ratio of Oliver's age to Glen's age is 8 : 3. Last year, their average age was 10. How old will Glen be in 7 years' time?
|
Oliver |
Glen |
Total |
Before |
8 u - 1 |
3 u - 1 |
20 |
Change |
+ 1 |
+ 1 |
|
After |
8 u |
3 u |
22 |
Total age of Oliver and Glen this year
= 8 u + 3 u
= 11 u
Total age of Oliver and Glen this year
= 2 x 10 + 1 + 1
= 20 + 2
= 22
11 u = 22
1 u = 22 ÷ 11 = 2
Glen's age in 7 years' time
= 3 u + 7
= 3 x 2 + 7
= 6 + 7
= 13
Answer(s): 13