Xavier's current age is 9 times as old as Zane's age years ago. Today, Zane's age is Xavier's age the same number of years ago. How old is Xavier's age now if the total of their current age is 70?
| |
Xavier |
Zane |
Difference |
Total |
| Before |
1 p |
1 u |
1 p - 1 u |
|
| Change |
+ ? |
+ ? |
|
|
| After |
9 u |
1 p |
9 u - 1 p |
70 |
Total age of Xavier and Zane today = 9 u + 1 p
9 u + 1 p = 70 --- (1)
The difference in Xavier's age and Zane'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 = 70
9 u + 5 u = 70
14 u = 70
1 u = 70 ÷ 14 = 5
Xavier's age now
= 9 u
= 9 x 5
= 45
Answer(s): 45
