Dylan's current age is 9 times as old as Jeremy's age years ago. Today, Jeremy's age is Dylan's age the same number of years ago. How old is Jeremy's age now if the total of their current age is 112?
| |
Dylan |
Jeremy |
Difference |
Total |
| Before |
1 p |
1 u |
1 p - 1 u |
|
| Change |
+ ? |
+ ? |
|
|
| After |
9 u |
1 p |
9 u - 1 p |
112 |
Total age of Dylan and Jeremy today = 9 u + 1 p
9 u + 1 p = 112 --- (1)
The difference in Dylan's age and Jeremy's age remains the same.
9 u - 1 p = 1 p - 1 u
9 u + 1 u = 1 p + 1 p
10 u = 2 p
5 u = 1 p
Substitute 1 p = 5 u into (1).
9 u + 1 p = 112
9 u + 5 u = 112
14 u = 112
1 u = 112 ÷ 14 = 8
Dylan's age now
= 112 - 9 u
= 112 - 9 x 8
= 112 - 72
= 40
Answer(s): 40
