Charlie's current age is 7 times as old as Gabriel's age years ago. Today, Gabriel's age is Charlie's age the same number of years ago. How old is Charlie's age now if the total of their current age is 77?
| |
Charlie |
Gabriel |
Difference |
Total |
| Before |
1 p |
1 u |
1 p - 1 u |
|
| Change |
+ ? |
+ ? |
|
|
| After |
7 u |
1 p |
7 u - 1 p |
77 |
Total age of Charlie and Gabriel today = 7 u + 1 p
7 u + 1 p = 77 --- (1)
The difference in Charlie's age and Gabriel'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 = 77
7 u + 4 u = 77
11 u = 77
1 u = 77 ÷ 11 = 7
Charlie's age now
= 7 u
= 7 x 7
= 49
Answer(s): 49
