John is 21 years older than his nephew. 3 years from now, his nephew will be
12 of his age while his niece will be
37 of his nephew. Express his niece’s present age as a fraction of John's present age. Leave your answer in its simplest form.
| |
John |
John's nephew |
John's niece |
Difference between
John and John's nephew |
| Before |
14 u - 3 |
7 u - 3 |
3 u - 3 |
21 |
| Change |
+ 3 |
+ 3 |
+ 3 |
|
After
|
2x7 |
1x7 |
|
|
| |
7x1 |
3x1 |
|
Comparing John, his nephew and his niece
in the end |
14 u |
7 u |
3 u |
7 u |
The repeated identity is the age of John's nephew. LCM of 1 and 7 is 7.
The difference in age between John and John's nephew remains unchanged.
Difference in age between John and John's nephew
= 14 u - 7 u
= 7 u
7 u = 21
1 u = 21 ÷ 7 = 3
His niece's present age
= 3 u - 3
= 3 x 3 - 3
= 9 - 3
= 6
John's present age
= 14 u - 3
= 14 x 3 - 3
= 42 - 3
= 39
His niece's present age as a fraction of John's present age
=
639=
213 Answer(s):
213 
