Japheth's current age is 5 times as old as Ken's age years ago. Today, Ken's age is Japheth's age the same number of years ago. How old is Ken's age now if the total of their current age is 48?
| |
Japheth |
Ken |
Difference |
Total |
| Before |
1 p |
1 u |
1 p - 1 u |
|
| Change |
+ ? |
+ ? |
|
|
| After |
5 u |
1 p |
5 u - 1 p |
48 |
Total age of Japheth and Ken today = 5 u + 1 p
5 u + 1 p = 48 --- (1)
The difference in Japheth's age and Ken's age remains the same.
5 u - 1 p = 1 p - 1 u
5 u + 1 u = 1 p + 1 p
6 u = 2 p
3 u = 1 p
Substitute 1 p = 3 u into (1).
5 u + 1 p = 48
5 u + 3 u = 48
8 u = 48
1 u = 48 ÷ 8 = 6
Japheth's age now
= 48 - 5 u
= 48 - 5 x 6
= 48 - 30
= 18
Answer(s): 18
