The ratio of Carl's age to Jenson's age is 3 : 1. Next year, their average age will be 21. How old will Carl be in 2 years' time?
|
Carl |
Jenson |
Total |
Before |
3 u |
1 u |
40 |
Change |
+ 1 |
+ 1 |
|
After |
3 u + 1 |
1 u + 1 |
42 |
Total age of Carl and Jenson this year
= 3 u + 1 u
= 4 u
Total age of Carl and Jenson this year
= 2 x 21 - 1 - 1
= 42 - 2
= 40
4 u = 40
1 u = 40 ÷ 4 = 10
Carl's age in 2 years' time
= 3 u + 2
= 3 x 10 + 2
= 30 + 2
= 32
Answer(s): 32