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"Who likes riddles?"

A mother is 21 years older than her son. In six years, she'll be five times older than him. Where is the father?

Answer below:










Let's call the age of the mother x and the age of the son y.

We can work out two equations from what we've been told.

x = y + 21

(Which is, the mother is 21 years older than the son)

x + 6 = 5(y + 6)

(Which is, in six years, the mother will be five times older.)

So if you just substitute x..

y + 21 + 6 = 5(y + 6)

y + 27 = 5y + 30

-3 = 4y

y = -3/4

But.. what does that mean? y = -3/4? It means years.

The son is -3/4 years. There are 12 months in a year, so, he's minus 9 months old.

Where's the father? Inside the mother.

its one of those immensely cryptic puzzles that i hate immensely. Totally unclear and fustrating.

Partly because its maths
Partly because it doesn't give you much to work on unless you understand the problem in the first place.


I'm more a logic puzzle guy, jigsaws, rubics cubes that sort of thing.

spoonbeast wrote:
> this is the type of maths thing that i dispise the most. Someone
> who won't give a straight answer.

Apologies, I don't understand what you mean by that

this is the type of maths thing that i dispise the most. Someone who won't give a straight answer.

hah, very good. Must remember that.

A mother is 21 years older than her son. In six years, she'll be five times older than him. Where is the father?

Answer below:










Let's call the age of the mother x and the age of the son y.

We can work out two equations from what we've been told.

x = y + 21

(Which is, the mother is 21 years older than the son)

x + 6 = 5(y + 6)

(Which is, in six years, the mother will be five times older.)

So if you just substitute x..

y + 21 + 6 = 5(y + 6)

y + 27 = 5y + 30

-3 = 4y

y = -3/4

But.. what does that mean? y = -3/4? It means years.

The son is -3/4 years. There are 12 months in a year, so, he's minus 9 months old.

Where's the father? Inside the mother.