A's age was 4 times that of b, 10 years ago. after 10 years his age will be twice as that of b, what is the present age of b
Answers
Answered by
0
the present age of b is 20 years
Answered by
1
Let A's present age be a
and B's present age be b
Ten years ago ,
a - 10 = 4 ( b - 10 )
a - 10 = 4b - 40
a - 4b - 10 + 40 = 0
a - 4b + 30 = 0 ..... ( i )
After ten years
a + 10 = 2 ( b + 10 )
a + 10 = 2b + 20
a - 2b + 10 - 20 = 0
a - 2b - 10 = 0 .... ( ii )
( for solution refer to the attachment )
Putting the value of b in ( ii )
a - 2b - 10 = 0
a - 2 × 20 - 10 = 0
a - 40 - 10 = 0
a = 50
So,
The present age of A is 50
and present age of B is 20
and B's present age be b
Ten years ago ,
a - 10 = 4 ( b - 10 )
a - 10 = 4b - 40
a - 4b - 10 + 40 = 0
a - 4b + 30 = 0 ..... ( i )
After ten years
a + 10 = 2 ( b + 10 )
a + 10 = 2b + 20
a - 2b + 10 - 20 = 0
a - 2b - 10 = 0 .... ( ii )
( for solution refer to the attachment )
Putting the value of b in ( ii )
a - 2b - 10 = 0
a - 2 × 20 - 10 = 0
a - 40 - 10 = 0
a = 50
So,
The present age of A is 50
and present age of B is 20
Attachments:
Similar questions