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How Many Mice?

Trick brain teasers appear difficult at first, but they have a trick that makes them really easy.


Puzzle ID:#42290
Fun:*** (3.03)
Difficulty:* (0.93)
Submitted By:RiddleMeThis91Aus****!




Mice are famous for their ability to multiply at breakneck speeds. The type of mouse we have here gives birth once a month, birthing 12 babies each time. Baby mice mature and can give birth two months after they are born.

You picked up one of these cute baby mice at the pet shop and brought it home the day after it was born. In 10 months from now, how many mice will you have?

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Jun 19, 2008

Did you get that from a game?
Jun 20, 2008

great teaser
Jun 20, 2008

Jun 20, 2008

Rats! You got SourDough good, you did! ARRRRRGGGGGHHH!!!

Jun 21, 2008

tht was a awsum teaser i actually got this one
Jun 22, 2008

Rats!I knew there was going to be a trick!How did I miss that?
Jun 23, 2008

Quickq, the category shouldve told u there was a trick!!

Nice teaser,...quite simple however! fun nonetheless....
Jun 25, 2008

great teaser, that got me!
Jun 25, 2008

wow i actually got that 1!!!
Jun 26, 2008

Fun! I think this was on Professor Layton and the Curious Village
Jun 26, 2008

Yeah,that's what I was talking about.He told me that he got it from a friend.
Jun 26, 2008

Jun 28, 2008

Cute teaser!! ---BUT --- One mouse certainly CAN give birth alone - She just needs another mouse to aid in CONCEIVING the next generation!
Jun 29, 2008

Due to my dislike of math, I looked for, and quickly found, the answer (which didn't include math!).
Jul 01, 2008

Good one!
Jul 01, 2008

unklemyke, it said it was a BABY mouse. I doubt that it has matured enough to be able to conceive.
Jul 03, 2008

You got me! Nice one XD
Jul 08, 2008

Yes, unklemyke, because you bought the BABY mouse the day after it was born, it couldn't be pregnant. It's only one day old, and the riddle states that these mice can conceive after two months.

Good teaser!
Jul 10, 2008

great teaser

could have been phrased a bit better, but still great
Jul 14, 2008

That teaser tricked me ok
Jul 15, 2008

I got it..quite simple
Jul 15, 2008

This was cute
Jul 17, 2008

$ourDough belted out a major guffaw with this one

Jul 20, 2008

This was stolen from:

Professor Layton And the Curious Village on the Nintendo DS.
Jul 20, 2008

Thank you, PhoenixW, for revealing what you claim to be the true source of this teaser.
Curious myself, I was prompted to read a review for PLATCV. Now I MUST get that game for my DS!
Jul 20, 2008

That was fantastic
kinda easy though i think i might have heard something like this before.
Jul 20, 2008

Nice teaser. Really hard, but I got it. Yay!!!
Jul 20, 2008

Very catchy but still easy if you just think about it. You know it is a riddle,not a math test.
Jul 20, 2008

Way too easy. Even if there hadn't been a trick you would still need to know the number of specifically female mice in each litter.
Jul 20, 2008

That was fun, and I GOT IT!!!

Hey, PhoenixW, you should just accuse someone of ROBBERY just because you saw the teaser in a different medium. The person who "made it", or submitted it to Braingle and got it accepted, apparently said to someone else that they got it from a friend. That is entirely possible. The friend may have seen it on "thatever show you're naming", and told it to RiddleMeThis.
In fact, it says in the credits "Submitted by:", not "created by", and as far as I know, it's totally legit on Braingle to submit a teaser that was on a game, or in a movie, etc.

Even if it wasn't OK, and even if Riddlemethis claimed to have "created" the teaser, and it was in a book of teasers, the submitter may not have known that, and may have made it up independently of another source, or gotten it from a friend who said it was OK with them to submit it as a teaser.

But even if they definitely did COPY it and it was somehow KNOWN they did, you don't just post "This was stolen from..."!!! You would PM a moderator or Jake from Braingle, and tell them what you suspected. Sorry I've gone on a bit here, but, it's really offensive to me when people just hurl an accusation at someone, in public, which isn't even true or is in question!!!

Once again, GREAT TEASER, thanks for submitting it, I'm going to see if I can trick some of my family with this one.

Jul 20, 2008

That was a geat teaser and thank you for it, I needed a good laugh.
Jul 20, 2008

Jul 20, 2008

I got this one in a split second. Too obvious. I can just picture people with pencil & paper trying to figure it out. Very funny, tricky but easy.
Jul 20, 2008

This was a good teaser.
And no mouse can reproduce
by its self
duhhhh! =]

-Dont even try to conclude
conceiving with another mouse either.
Jul 20, 2008

Good practice for state board exams. I am always telling the students to read the question carefully!
Jul 20, 2008

I figured this out right away. In reality though, a one day old mouse would die of starvation, since it would not be able to get milk from its mother. I am sure it needs to be nursed for at least a week or two, as I have seen baby mice with their mother, and they were over a day old! But I'm nitpicking!
Jul 20, 2008

Sweet. I got it
Jul 20, 2008

I got it!
Yes, it was easy; but I completely miss some of these that are easy. Good one. Thanks!
Jul 20, 2008

Dang. That got me. I started to do the math, then said, "Ugg. I give up. I'm just gonna look at the answer." When I saw it was one, I went crazy.
Jul 20, 2008

I got a good laugh out of this one. Very clever no matter who thought of it first. Thanks for posting.
Jul 20, 2008

Yeah! I got this one!!!
Jul 21, 2008

I asked myself, What was the catgory? That usually does it for me in this category.
Aug 17, 2008

i knew it was one but i thought it was because boy mice can't give birth like in the paragragh it said boy mice mature and can GIVE BIRTH in two months so yepp.
Aug 31, 2008

Sep 08, 2008

I got this one easily. But I had to remind myself that it was a trick question. Very good.
Oct 02, 2008

I forgot it was in the trick catagory... ya, i said 60
(user deleted)
Oct 08, 2008

lol i should smack you i wrote it all out
Oct 10, 2008

Concerning the comment about this being taken from Professor Layton:

The wording is exactly the same, so yes, I assume the author of this puzzle took it straight from that game. However, I'm sure this puzzle has existed for years in many forms.
Oct 13, 2008

Nov 02, 2008

"In fact, it says in the credits "Submitted by:", not "created by", and as far as I know, it's totally legit on Braingle to submit a teaser that was on a game, or in a movie, etc."

I haven't looked through the TOS of this site yet, but I doubt that out and out plagarism is allowed.

"Even if it wasn't OK, and even if Riddlemethis claimed to have "created" the teaser, and it was in a book of teasers, the submitter may not have known that, and may have made it up independently of another source, or gotten it from a friend who said it was OK with them to submit it as a teaser."

That's not what the situation is. This is a verbatim word for word transcription from Professor Layton. These puzzles, with this specific sequence of words, belong to Level 5. If someone wrote a teaser LIKE this one (and there's been many forms of this particular teaser, so this isn't just a hypothetical) no one would have anything to say about it. This is a word for word copy, right down to the title.

Nevertheless, I loved it in Layton, and I still love it. Great teaser.
Nov 12, 2008

I said one, cause it was male. As for the whole fiasco of where this came from, how do we know the people who put it into that game made it up? Riddles & teasers have been around WAAY longer than video games - this could've been around for centuries! Thanks for submitting it, either way!
Nov 27, 2008

Dec 08, 2008

I'm just glad i figured it out before I did the math.
Dec 22, 2008

This was used on The Curious Village, but is a really old teaser. It can be used anywhere, and it is fine here.
Jan 02, 2009

That was really easy, I got it immediatly
Jan 12, 2009

I love trick teasers they're always soooooo easy.... of course a mouse can't have babies by itself! its not bacteria ya know
Jan 12, 2009

i actually had the paper and pencil out and the problem figured out before i saw that only one mouse was bought. how embarassing
Jan 28, 2009

I thought the anser was you cant have mice (like giving birth)
Feb 14, 2009

Isn't it from 'Proffesor Layton and The Curious Village'???
Apr 02, 2009

It's easy-peasy for people who can be very sarcastic. Like me. Nice trick though (and I'm not being sarcastic)
Apr 06, 2009

that was VERY cute!!!

whats with all the nitpicking people???
Apr 07, 2009

So you made me go through and do all the math only to realize I did not have to after I finish!!! Arrg! Cool though.
Jun 14, 2009

Great Teaser, and I got it.
Jul 06, 2009

i actually attempted to solve this mathematically, spending 15 minutes before i gave up and clicked answer.

stupid me.
Aug 30, 2009

I thought that it was 108, and it was trick because people might put 120. Great teaser!
Oct 20, 2009

very well
Jan 05, 2010

I just guessed 1 and I got it right.

The category gave it away..
Feb 17, 2010

Saw this before in Professor Layton, but still a great teaser
Jul 22, 2010

LOL Great teaser
Jun 02, 2011

The mouse could have died.
Jul 20, 2011

Quite easy, but heard of a tribble?
Jul 20, 2011

In my apartment the answer would be several grey and white mice. I'd buy a white one and it would mate with the grey ones we are trying to get rid of.
Jul 20, 2011

Fairly easy teaser but still a good one.

Tribbles hate Klingons and Klingons hate tribbles.
Jul 20, 2011

The answer now is zero. Since this teaser is three years old the mouse died of old age.
Jul 20, 2011

I've said it before, and I'll say it again (probably in two or three years! ) The teaser was a good one and made me smile! BUT the comments made me laugh out loud!!!
Jul 20, 2011

I got it right away, but it felt familiar, so I'm sure I've heard it years before (years before Prof. Leyton came out, which I've never played). It reminds me of the question about if a rooster's egg will roll to the left or right if it lays the egg on the peak of a roof.

It certainly pays to read a question carefully - I once had a maths teacher who got frustrated with no one following directions, so he handed out a 100 question test with extremely complicated problems, which clearly could not be finished within a 40-minute class. Eventually, several students began to put their heads on their desks, with smiles on their faces, really panicking those of us still trying to figure out even the initial calculus problems. Eventually, everyone figured it out when we went back and reread the directions at the top of the test (which he clearly told us to read as he handed the tests out), which told us to solve the last five problems and put our heads on our desks when finished (and naturally, the last five questions of the test involved embarassingly simple maths like 5-4 and 2+3).

I've been very good at trick questions since that day!
Jul 20, 2011

Although I worked this one out as being only one (or possibly none as the baby mouse was taken so early from its mother), I thought I would crunch the numbers anyway:
Presuming the original mouse is female, a male is introduced only for one night once the mouse is two months old, and that each litter produces 6 of each gender then the final number after just 10 months would be a staggering 52,545!!! Phew.
Jul 20, 2011

Correction - Small mistake during the process , actual answer would be 82,273
Jul 22, 2011

Nice teaser..really got me guud..
Jul 22, 2011

Nice teaser..really got me guud..
Jul 29, 2011

well, DUH! You only bought ONE mouse!
Nov 18, 2011

if it did have babies you would have 120 mice
Jun 15, 2012

Very easy ;)
Jul 20, 2014

OH!! Hahaha!
Jul 20, 2014

G'mprnin',mates. At least for those of you in America. Nice day here, too.

And nice comments. Not many, though.

We need to find ways to encourage visits, comments, and votes.

Take a look at the count at the bottom of this page. It is probably in the 300's somewhere.

That's REALLY low to sustain a site of this calibre. We need to do some work to save Braingle.

And ... we will have our first FULL month of data to report - about mid-August - but I'll be here daily (maybe ) to keep you posted.

Thanks for reading.

Jul 20, 2014

I thought DOEHEAD had the best answer in 2011. But I did have it right.
Jul 20, 2014

If I hadn't read it twice I would still be counting fingers and toes.
Jul 20, 2014

Love this one. Thanks for posting! Love the comments, too!
Jul 20, 2014

Got it! These types are always fun.

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