Where Is the Father in This Age-Related Riddle?

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masters1
I posted this a long time ago, but maybe some of you might have missed it.

The mother is 21 years older than the child.
6 years from now, the mother will be 5 times as old as the child.

Question : Where is the father?
 
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I solved this problem/joke way back then.
It's one of my favorites.

I think the punchline is very funny.
 
masters said:
I posted this a long time ago, but maybe some of you might have missed it.

The mother is 21 years older than the child.
6 years from now, the mother will be 5 times as old as the child.

Question : Where is the father?


x = mother age
y = childs age

$x = 21 + y$ and $y + 6 = (x + 6)/5$

So $y = x - 21$ by substitution we have $x - 21 + 6 = (x + 6)/5\Leftrightarrow x - x/5 = 15 + 6/5 \Leftrightarrow x(4/5) = 81/5\Leftrightarrow x = 81/4\approx 20.25$

So the father is having "relations" with the mother.
 
c = child; so mother = c+21

c+21 + 6 = 5(c + 6)

c = -3/4

9 months BEFORE birth...so father is "creating" with mother! Real cute.
 
Wilmer said:
. . .

9 months BEFORE birth...so father is "creating" with mother! Real cute.

Isn't the father procreating with the mother?