The ratio of Albert's age to Japheth's age is 4 : 1. Last year, their average age was 19. How old will Japheth be in 3 years' time?
|
Albert |
Japheth |
Total |
Before |
4 u - 1 |
1 u - 1 |
38 |
Change |
+ 1 |
+ 1 |
|
After |
4 u |
1 u |
40 |
Total age of Albert and Japheth this year
= 4 u + 1 u
= 5 u
Total age of Albert and Japheth this year
= 2 x 19 + 1 + 1
= 38 + 2
= 40
5 u = 40
1 u = 40 ÷ 5 = 8
Japheth's age in 3 years' time
= 1 u + 3
= 1 x 8 + 3
= 8 + 3
= 11
Answer(s): 11