Vaidev's current age is 7 times as old as Fred's age years ago. Today, Fred's age is Vaidev's age the same number of years ago. How old is Fred's age now if the total of their current age is 55?
| |
Vaidev |
Fred |
Difference |
Total |
| Before |
1 p |
1 u |
1 p - 1 u |
|
| Change |
+ ? |
+ ? |
|
|
| After |
7 u |
1 p |
7 u - 1 p |
55 |
Total age of Vaidev and Fred today = 7 u + 1 p
7 u + 1 p = 55 --- (1)
The difference in Vaidev's age and Fred's age remains the same.
7 u - 1 p = 1 p - 1 u
7 u + 1 u = 1 p + 1 p
8 u = 2 p
4 u = 1 p
Substitute 1 p = 4 u into (1).
7 u + 1 p = 55
7 u + 4 u = 55
11 u = 55
1 u = 55 ÷ 11 = 5
Vaidev's age now
= 55 - 7 u
= 55 - 7 x 5
= 55 - 35
= 20
Answer(s): 20
