The ratio of Fabian's age to Carl's age is 9 : 2. Last year, their average age was 21. How old will Carl be in 10 years' time?
|
Fabian |
Carl |
Total |
Before |
9 u - 1 |
2 u - 1 |
42 |
Change |
+ 1 |
+ 1 |
|
After |
9 u |
2 u |
44 |
Total age of Fabian and Carl this year
= 9 u + 2 u
= 11 u
Total age of Fabian and Carl this year
= 2 x 21 + 1 + 1
= 42 + 2
= 44
11 u = 44
1 u = 44 ÷ 11 = 4
Carl's age in 10 years' time
= 2 u + 10
= 2 x 4 + 10
= 8 + 10
= 18
Answer(s): 18