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.
How old is the child?
Where's the father?
Try first, before you check!
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
C + 21 + 6 = (C + 6) x 5
C + 27 = 5C + 30
-3 = 4C
C = -3/4
The child is -3/4 years old, it'll be born in 9 months.
Right now, the father is on top of the mother.
LOL!
Do the Math!
Subscribe to:
Post Comments (Atom)
1 comment:
Another way of solving this is to realize that the mother will only be 5 times older than the child at one point in the child's lifetime, and always 21 years older.
Let Mom be m and Child be c.
m = 21 + c
At the point which the mother is 5 times older than the child:
5c = 21 + c
c = 5.25
Since this will happen 6 years from now
c = 5.25 -6 or - 0.75 yrs old.
Post a Comment