Fun Puzzle

[clixpix]

Originally Posted by KristyKitty

oh I see. I must be really dumb because I still don't get it!

It never says whether her house or her neighbors house is even or odd. So couldn't her neighbor's house easily be 14, and her house be 12 or 16?

I'm sorry I'm so dumb and need things spelled out!

You're not dumb at all...none of the rest of us could figure it out, so Butzie called in a ringer!

I had the same questions that you did...why not the other combinations? That's where logic and math had to both be used:

*He got his first clue, and realized that there were several combinations that ended up at 36 when multiplied together, so he asked for another clue. He needed another clue.

*The second clue said that the ages added together equal the house number next door, so he went and got that. The house number narrowed down his possibilities, but since he needed another hint, we know that although the possibilities were narrowed down, there were at least two possible combinations left. Of all of the possible combinations from clue 1, only two of them, when added together, equaled the same number. Those combinations were the ages 1, 6, 6, and 2, 2, 9. The only way to know which one is with another hint.

*The third hint was that the "eldest played piano". Like Butzie's DH said, that tells us that there is only one eldest. If she had said "one of the eldest plays piano", we would know that there were two eldest. So since there is only one eldest, it has to be the combination of 2, 2, 9. It's the fact that he needed all three clues is the reason that 2, 2, 9 is the answer.

Does that help?

My apologies to Butzie's DH for saying the same thing, but taking all the math lingo out of it for those of us who go all fuzzy when words like "integers" start being bandied about!

 

[kristykitty]

Originally Posted by clixpix

You're not dumb at all...none of the rest of us could figure it out, so Butzie called in a ringer!

I had the same questions that you did...why not the other combinations? That's where logic and math had to both be used:

*He got his first clue, and realized that there were several combinations that ended up at 36 when multiplied together, so he asked for another clue. He needed another clue.

*The second clue said that the ages added together equal the house number next door, so he went and got that. The house number narrowed down his possibilities, but since he needed another hint, we know that although the possibilities were narrowed down, there were at least two possible combinations left. Of all of the possible combinations from clue 1, only two of them, when added together, equaled the same number. Those combinations were the ages 1, 6, 6, and 2, 2, 9. The only way to know which one is with another hint.

*The third hint was that the "eldest played piano". Like Butzie's DH said, that tells us that there is only one eldest. If she had said "one of the eldest plays piano", we would know that there were two eldest. So since there is only one eldest, it has to be the combination of 2, 2, 9. It's the fact that he needed all three clues is the reason that 2, 2, 9 is the answer.

Does that help?

My apologies to Butzie's DH for saying the same thing, but taking all the math lingo out of it for those of us who go all fuzzy when words like "integers" start being bandied about!

Oh I think I get it now, thanks!

That's a strange puzzle, you sort of have the assume exactly what the guy was thinking. I didn't even pay attention to the word "needed" and that this meant he had narrowed it down to 2 choices. I think that's a little bit of a jump to get to that assumption. But whatever

I understood the first and third clue, the 2nd one I was having some trouble on.

I'm going to give this to my dad, he's a calculus professor. He loves things like this!

Thanks for explaining! I am just going to assume a lot of people had the same questions as me

 

[clixpix]

Originally Posted by KristyKitty

Oh I think I get it now, thanks!

I didn't even pay attention to the word "needed" and that this meant he had narrowed it down to 2 choices. I think that's a little bit of a jump to get to that assumption.

It's not an assumption. Since he asked for a third clue, you know that by using the first two clues he has narrowed it down to at least two choices. Of all of the combinations you can find for clue 1, only two of them, when added together, equal the same number.

I hope your dad enjoys the puzzle!

 

[kristykitty]

Originally Posted by clixpix

It's not an assumption. Since he asked for a third clue, you know that by using the first two clues he has narrowed it down to at least two choices. Of all of the combinations you can find for clue 1, only two of them, when added together, equal the same number.

I hope your dad enjoys the puzzle!

Oh okay, thanks again! I think I might finally really get it

I love things like this, although if I don't get it then I have to sit there forever until I figure it out.

I'm sure my dad will love it. He calls people up and they solve these puzzles together for fun on the weekends

He's a big nerd.

 

[algebrapro18]

A little bit of math is beeing skirted around here but I'm to lazy to put it up, you guys figured it out which I am happy about.

Does your dad know much about number theory? If he enjoys it he might also want to read In Code, its really really good. Its bascialy about a 16 year old girl who single handedly changed how cryptography and encoding of messages is done. Its really inspiring but it also makes me feel like I am a little dumb for not being able to do the same thing at 6 years older than her.

 

[fwan]

I am so glad i dont teach this stuff!

 

[calico2222]

There is a reason I majored in English and not math. But the logic behind this is fascinating! But, my head hurts now.

 

[carolpetunia]

Ah! It was the idea of "only one eldest" that escaped me! But I don't feel so bad, since it took an MIT genius to figure it out.

 

[butzie]

Originally Posted by algebrapro18

A little bit of math is beeing skirted around here but I'm to lazy to put it up, you guys figured it out which I am happy about.

Does your dad know much about number theory? If he enjoys it he might also want to read In Code, its really really good. Its bascialy about a 16 year old girl who single handedly changed how cryptography and encoding of messages is done. Its really inspiring but it also makes me feel like I am a little dumb for not being able to do the same thing at 6 years older than her.

DH is dear hubby, not dad. My dad only graduated from HS.

Originally Posted by KristyKitty

But why does the sum have to equal 13? It doesn't say what the house number has to be.

It could be 9,4, and 1. She said "my eldest plays piano". That doesn't mean the younger siblings have to be the same age.

So confused!

Originally Posted by kluchetta

Why not 9, 4 and 1?

Because they have to be prime factor. The prime factors of 36 are 3, 3, 2, 2, 1 so we look for 2 combinations of these that add to the same number and only two sets do:

9, 2, 2 - sum 13
6, 6, 1 - sum 13

That is where the 13 comes from; it has nothing to do with house numbers.

6,6,1 doesn't have an eldest child, only 9, 2, 2 does.

 

[clixpix]

Originally Posted by butzie

DH is dear hubby, not dad. My dad only graduated from HS.

I think he was directing that to KristyKitty who said her dad would enjoy the puzzle and is a calculus teacher.

 

[kluchetta]

Originally Posted by butzie

Because they have to be prime factor. The prime factors of 36 are 3, 3, 2, 2, 1 so we look for 2 combinations of these that add to the same number and only two sets do:

9, 2, 2 - sum 13
6, 6, 1 - sum 13

That is where the 13 comes from; it has nothing to do with house numbers.

6,6,1 doesn't have an eldest child, only 9, 2, 2 does.

Oh, I got it right after I posted. I was adding 9+4+1=13 LOL. If that were true I would've had a chance, but

I can't even add!

 

[kristykitty]

Originally Posted by algebrapro18

A little bit of math is beeing skirted around here but I'm to lazy to put it up, you guys figured it out which I am happy about.

Does your dad know much about number theory? If he enjoys it he might also want to read In Code, its really really good. Its bascialy about a 16 year old girl who single handedly changed how cryptography and encoding of messages is done. Its really inspiring but it also makes me feel like I am a little dumb for not being able to do the same thing at 6 years older than her.

hmm, I'm not sure if he knows about number theory, probably but I will ask him. He's already is bed right now

so perhaps tomorrow

and wow at the 16 yr old girl. I guess some people are just prodigies.