Solve the Brain Teaser: 40 Heads, 100 Legs - How Many Kids and Dogs?

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The discussion revolves around a mathematical problem posed by a teacher who counts a total of 40 heads and 100 legs among kids and dogs in a park. The initial solution presented is 30 kids and 10 dogs, but participants are encouraged to find another valid answer. Some contributors express confusion over the problem's wording, suggesting it may imply a trick or that the teacher might be including her own legs and head in the count. Various interpretations arise, including the possibility of counting other entities or miscounting. Ultimately, suggestions for alternative answers include 29 kids and 10 dogs, with the teacher's presence accounted for. The conversation highlights the ambiguity in the problem's phrasing and the potential for multiple interpretations.
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A teacher is sitting at a park and counts all the kids and all the dogs. She comes to a total of 40 head and 100 legs. How many kids and dogs are there?

There is more than one answer. the first one is 30 kids and 10 dogs.

Find ONE more answer!

There is no trick animal (ie: a three legged dog or two headed kid.).

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Can anyone figure this out? I can't. please let me know the answer.
 
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This just leads to two equations and two unknowns. So mathematically speaking there is one unique solution.
Please let us know if you find otherwise.
 
Are there any goats?
 
mathematically speaking , another answer is not possible , may be some trick is involved
 
I will.. I know there is some kind of trick to it... its racking my brain trying to think of it!
 
2k+4d=100
k+d=40

One answer. This must be a trick question then. Let's see, no trick animals allowed, so it must be a trick to how or what she's counting.
 
My solution:
40 kids, 10 of which are puppies
EOM
 
GraphicSpaz said:
A teacher is sitting at a park and counts all the kids and all the dogs. She comes to a total of 40 head and 100 legs. How many kids and dogs are there?

There is more than one answer. the first one is 30 kids and 10 dogs.

Find ONE more answer!

There is no trick animal (ie: a three legged dog or two headed kid.).

---------

Can anyone figure this out? I can't. please let me know the answer.
Is this the problem EXACTLY as given to you?
 
GraphicSpaz said:
A teacher is sitting at a park and counts all the kids and all the dogs. She comes to a total of 40 head and 100 legs. How many kids and dogs are there?

The answer is indeed a trick, assuming that:
1) All "kids" she counts have 2 legs and 1 head
2) All "dogs" she counts have 4 legs and 1 head
3) She is not including anything else in her count (IE, only the legs and heads of kids and dogs in the park, and not, say, her own legs and head)
4) Her count is accurate
5) "Kids" and "dogs" are constant throughout the problem
6) Numbers provided are in base 10

The question is also poorly worded. She is not, in fact, counting "all the kids and all the dogs". She is actually counting all the kids' legs, kids' heads, dogs' legs, and dogs' heads. The fact that she counts "40 head" is assumably just a typo (should be "40 heads", but that's easily forgiveable), and if you're REALLY being persnickity, it should specify that the teacher counts all the heads and legs "in the park", and should ask how many kids and dogs are "in the park", rather than just how many there are.

My guess is the answer they're looking for is 29 kids and 10 dogs, but she counts her *own* legs and head.

DaveE
 
  • #10
maybe dogs mean ugly kids?
 
  • #11
davee123 said:
The fact that she counts "40 head" is assumably just a typo
I wondered about this too. I tested a scenario based on the premise there were 40 'head of cattle' in the park, but I didn't get sensible results.
 
  • #12
What's red and has got two legs?
 
  • #13
You know, nowhere does it say she counted ONLY kids and dogs. Maybe there was a table. Or better yet, something common in a park (that is not an animal) but has both a head and a number of legs...
 
  • #14
I suppose we could be overlooking the obvious:

There are 10 dogs, 29 kids, 1 teacher.

40 heads, 100 legs.
 
  • #15
No-one wants to know the answer :(

J77 said:
What's red and has got two legs?
Half a dog! :biggrin:
 
  • #16
J77 said:
Half a dog! :biggrin:

Lol. Its funnier the way I first heard it.

What has two legs and bleeds?
 
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