Simon's current age is 3 times as old as Seth's age years ago. Today, Seth's age is Simon's age the same number of years ago. How old is Simon's age now if the total of their current age is 45?
| |
Simon |
Seth |
Difference |
Total |
| Before |
1 p |
1 u |
1 p - 1 u |
|
| Change |
+ ? |
+ ? |
|
|
| After |
3 u |
1 p |
3 u - 1 p |
45 |
Total age of Simon and Seth today = 3 u + 1 p
3 u + 1 p = 45 --- (1)
The difference in Simon's age and Seth's age remains the same.
3 u - 1 p = 1 p - 1 u
3 u + 1 u = 1 p + 1 p
4 u = 2 p
2 u = 1 p
Substitute 1 p = 2 u into (1).
3 u + 1 p = 45
3 u + 2 u = 45
5 u = 45
1 u = 45 ÷ 5 = 9
Simon's age now
= 3 u
= 3 x 9
= 27
Answer(s): 27
