Brain Teasers

[schielrn]

I'm not sure I am understanding this as there could be more than one possible answer in my mind? Cause as Sandeep said the only evidence we have is that the product of the 3 children is 36. Which could be split in a few different ways? But 2 of the 3 ways I was thinking would involve twins.

 

[Scott Huish]

If we assume whole number ages, my guess is 1,4,9 and the door number is 14.

 

[pgc01]

the only evidence we have is that the product of the 3 children is 36.

Hi schielrn

No, we also know that the sum of the ages must be equal to the number on the door. So, not any anwer will do.

 

[pgc01]

If we assume whole number ages, my guess is 1,4,9 and the door number is 14.

As you state it it's only a guess. You must prove that that's the answer.

 

[yytsunamiyy]

I admit to the asking aunty G after racking my brain. Interesting solution. Thanks for the knot in my brain pgc

 

[schielrn]

If we assume whole number ages, my guess is 1,4,9 and the door number is 14.

What about 2, 3 and 6? And the door number being 11?

 

[Scott Huish]

Yeah, I thought of that too.

Also 3,3,4, Door #10

 

[schielrn]

I believe it to be actually 2,2,9. Based on the clues given and that each clue must eliminate something. But to Oaktree's point one is one twin would actually be older than the other. So it could have been 1,6,6 but it is 2,2,9.

There are 8 possiblities:

Excel Workbook
	A	B	C	D	E
1	Kid 1	Kid 2	Kid 3	sum	product
2	1	1	36	38	36
3	1	2	18	21	36
4	1	3	12	16	36
5	1	4	9	14	36
6	1	6	6	13	36
7	2	2	9	13	36
8	2	3	6	11	36
9	3	3	4	10	36
Sheet1

But of those 8 only 2 result in the same door number, so that must be the door number, otherwise what is the point of that clue. Then if there is an eldest child, the twins could not be the oldest, so it must be 2, 2 and 9. Is that correct?

 

[pgc01]

I believe it to be actually 2,2,9. Based on the clues given and that each clue must eliminate something. But to Oaktree's point one is one twin would actually be older than the other. So it could have been 1,6,6 but it is 2,2,9.

There are 8 possiblities:

Excel Workbook
	A	B	C	D	E
1	Kid 1	Kid 2	Kid 3	sum	product
2	1	1	36	38	36
3	1	2	18	21	36
4	1	3	12	16	36
5	1	4	9	14	36
6	1	6	6	13	36
7	2	2	9	13	36
8	2	3	6	11	36
9	3	3	4	10	36
Sheet1

But of those 8 only 2 result in the same door number, so that must be the door number, otherwise what is the point of that clue. Then if there is an eldest child, the twins could not be the oldest, so it must be 2, 2 and 9. Is that correct?

Yes. We've got a solution. And Schielrn is the winner!

If fact, we don't know the numer on the building door, but Mary does!

This means that if the number on the door of the building was different from 13 she would immediately know the ages of the 3 kids. Since she still couldn't tell the ages, this means that the sum of the ages was 13, with the 2 possible solutions (1,6,6) or (2,2,9).

Now the second clue tells us that there was 1 eldest child. We know that last time Mary was with the couple the eldest daughter was there, we infer that there is one child older that the others, or else Jack would say "one of the twins" instead of "my eldest", and also Mary would answer "I remember now, you had twins", you don't ususally forget that your friend has twins.
Anyway, so that there would be no doubts I posted in the answer to Oaktree that at the time of their last meeting Jack "only had 1 kid, 2 or 3 yours old."

So, in concusion, as Schielrn said, the answer is (2,2,9).

Cheers
Thanks for trying

 

[Scott Huish]

I don't quite follow this:

This means that if the number on the door of the building was different from 13 she would immediately know the ages of the 3 kids.

If the number wasn't 13 there are more possibilities, how could she possibly know?