The ratio of Simon's age to Jeremy's age is 5 : 2. Last year, their average age was 20. How old will Jeremy be in 10 years' time?
|
Simon |
Jeremy |
Total |
Before |
5 u - 1 |
2 u - 1 |
40 |
Change |
+ 1 |
+ 1 |
|
After |
5 u |
2 u |
42 |
Total age of Simon and Jeremy this year
= 5 u + 2 u
= 7 u
Total age of Simon and Jeremy this year
= 2 x 20 + 1 + 1
= 40 + 2
= 42
7 u = 42
1 u = 42 ÷ 7 = 6
Jeremy's age in 10 years' time
= 2 u + 10
= 2 x 6 + 10
= 12 + 10
= 22
Answer(s): 22