07-17-2008, 05:23 PM
Specification:
The mum is 21 years older than the child.
In 6 years from now the mum will be 5 times as old as the child.
Question:
Where's the father?
Try first, before you check the answer below!
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Solution:
The mum is 21 years older than the child.
M = C + 21
In 6 years from now the mum will be 5 times as old as the child.
M + 6 = (C + 6) x 5
Hence,
C + 21 + 6 = (C + 6) x 5
C + 27 = 5C + 30
-3 = 4C
C = -3/4
The child is -3/4 years old right now,
So it'll be born in 9 months.
Answer:
So right now, the father is on top of the mother.
The mum is 21 years older than the child.
In 6 years from now the mum will be 5 times as old as the child.
Question:
Where's the father?
Try first, before you check the answer below!
*
*
*
*
*
*
Solution:
The mum is 21 years older than the child.
M = C + 21
In 6 years from now the mum will be 5 times as old as the child.
M + 6 = (C + 6) x 5
Hence,
C + 21 + 6 = (C + 6) x 5
C + 27 = 5C + 30
-3 = 4C
C = -3/4
The child is -3/4 years old right now,
So it'll be born in 9 months.
Answer:
So right now, the father is on top of the mother.