The ratio of Seth's age to George's age is 9 : 5. Last year, their average age was 20. How old will George be in 5 years' time?
| |
Seth |
George |
Total |
| Before |
9 u - 1 |
5 u - 1 |
40 |
| Change |
+ 1 |
+ 1 |
|
| After |
9 u |
5 u |
42 |
Total age of Seth and George this year
= 9 u + 5 u
= 14 u
Total age of Seth and George this year
= 2 x 20 + 1 + 1
= 40 + 2
= 42
14 u = 42
1 u = 42 ÷ 14 = 3
George's age in 5 years' time
= 5 u + 5
= 5 x 3 + 5
= 15 + 5
= 20
Answer(s): 20
