The ratio of Julian's age to Peter's age is 7 : 1. Last year, their average age was 19. How old will Peter be in 10 years' time?
| |
Julian |
Peter |
Total |
| Before |
7 u - 1 |
1 u - 1 |
38 |
| Change |
+ 1 |
+ 1 |
|
| After |
7 u |
1 u |
40 |
Total age of Julian and Peter this year
= 7 u + 1 u
= 8 u
Total age of Julian and Peter this year
= 2 x 19 + 1 + 1
= 38 + 2
= 40
8 u = 40
1 u = 40 ÷ 8 = 5
Peter's age in 10 years' time
= 1 u + 10
= 1 x 5 + 10
= 5 + 10
= 15
Answer(s): 15
