This is one tough question! Especially for a 5th grader!
By ahgong
@ahgong (10064)
Singapore
March 24, 2009 9:13pm CST
Took me a long time to figure out the correct answer!
And mind you, I did well in math in all my years in school!
It is not at trick question. And the answer is achievable if you give it some time.
But as a 5th grader question, it ain't as easy as it looks! 
I will post the answer on my blog on the 30th of March if you are interested to find out.
But do give it a go. It is quite fun. And it really, and I mean, REALLY, makes you flex your brain muscle to get it right!
[b]
[i]This is not a trick question. This is a real math problem so don't say that a bus has no legs.
There are 7 girls in a bus.
Each girl has 7 backpacks.
In each backpack, there are 7 big cats.
For every big cat there are 7 little cats.
Question: How many legs are there in the bus?
*assuming there's no bus driver.
[/i][/b]
I cannot imagine how this could baffle an adult like me. And it is suppose to be a fifth grader question! Goodness! I am so out of touch with the things that a grade school kid is learning these days!
I will post the answer on my blog on the 30th of March if you are interested to find out.
But do give it a go. It is quite fun. And it really, and I mean, REALLY, makes you flex your brain muscle to get it right!
[b]
[i]This is not a trick question. This is a real math problem so don't say that a bus has no legs.
There are 7 girls in a bus.
Each girl has 7 backpacks.
In each backpack, there are 7 big cats.
For every big cat there are 7 little cats.
Question: How many legs are there in the bus?
*assuming there's no bus driver.
[/i][/b]
I cannot imagine how this could baffle an adult like me. And it is suppose to be a fifth grader question! Goodness! I am so out of touch with the things that a grade school kid is learning these days!9 people like this
34 responses
@pentaluda0878 (118)
• United States
25 Mar 09
Ok lets see I've done this before
7 girls= 14 legs
each girl has 7 backpacks each containing 7 cats so each girl has 49 cats
49 cats= 196
each cat has 7 kittens so 343 kittens
343 kittens=1372
14+196+1372= 1582 legs
and for those ignoring the backpacks read the question!!!!!!
@pentaluda0878 (118)
• United States
25 Mar 09
haha I actually think I'm wrong my number is to low but still the backpacks matter!!!!
3 people like this
@reichiru (748)
• Canada
26 Mar 09
This isn't that hard, is it?
7 girls x 2 legs = 14 legs total
7 girls x 7 backpacks = 49 backpacks
49 backpacks x 7 big cats = 343 big cats
343 big cats x 4 legs = 1372 legs
343 big cats x 7 little cats = 2401 little cats
2401 little cats x 7 legs = 9604 legs
9604 + 1372 + 14 = 10990 legs total
It only took me a few minutes to figure out 
3 people like this
@ahgong (10064)
• Singapore
2 Apr 09
Yep. And reichiru's workings is very similar to the way I worked out mine.
I posted the answer in my blog. As well as a picture to illustrate my point. Do go and check it out!
The other way is to check out this picture I posted on mylot.
http://www.mylot.com/w/image/2167467.aspx
@rymebristol (1808)
• Philippines
25 Mar 09
my answer is 14...woah..."NOSE BLEED"
HOPE THAT I GOT THAT RIGHT...the question is "how many legs in the bus,well there are 7 girls, so that makes 14 legs. right?
2 people like this
@rymebristol (1808)
• Philippines
25 Mar 09
oh crap, i should read their answer first before i posted this..what a shame hahaha..and to think that i am the 31st to make a response hahaha
2 people like this
@Jae2619 (1482)
• United States
25 Mar 09
I suck at math and I had to ask my husband who's the math whiz to help me figure this out, lol..
Break it down to each book sack, so each book sack has 28 big cat ( 7x4) legs and 196 (7x7x4)little cat legs which equals 224.
7 girls x 7 booksacks = 49 booksacks
224 legs in each booksack x 49 booksacks = 10,976 total cat legs
10,976 total cat legs + 14 girl legs = 10,990 total legs on the bus!
@sceptile_ex (97)
•
25 Mar 09
2 minutes because I have to use mental calculation, no calculator.
2 people like this
@youless (112710)
• Guangzhou, China
25 Mar 09
You are right. This sounds very complicated and I am wondering whether my answer is correct. I am not good at maths:)
7 x 7 x 4 (cat legs) =196
7 x 2 (girls' legs) = 14
total: 196 + 14 = 210
So is it totally 210 legs? I can never dare to look down upon pupils as actually they know more than me:)
I love China
@kun2349 (23381)
• Singapore
25 Mar 09
lol =D I"m too lazy and in a rush now, thus i wont work out the exact amount of legs in here.. From what i roughly guessed, it should be more than 400 and less and 500.. lol =D
Why is the math problem so hard nowadays?? ON top of that, the figures are so big somemore.. lol =D Worse is that when they are not allowed to used calculators.. lol =D
@maxilimian (3099)
• Indonesia
25 Mar 09
Waa interesting i have a question, did you ask the girls leg or all of the legs, including the cat leg's?
i have a question, did you ask the girls leg or all of the legs, including the cat leg's? 1 person likes this
@maxilimian (3099)
• Indonesia
25 Mar 09
Haha sorry, too busy to answer it ahgong
i may try 7 girls = 7x2 = 14 legs
7 cats = 7x4 = 28 legs
For every big cats 7 little cats = 7x7x4 = 196 legs
Total = 14+28+196 = 238 legs including cats and the girls
Am i right? sorry i can't post it immediately, things .. walking arround ... you know hehe even i'm almost forget if i post here 
i may try 7 girls = 7x2 = 14 legs
7 cats = 7x4 = 28 legs
For every big cats 7 little cats = 7x7x4 = 196 legs
Total = 14+28+196 = 238 legs including cats and the girls
Am i right? sorry i can't post it immediately, things .. walking arround ... you know hehe even i'm almost forget if i post here 1 person likes this
@sanuanu (11235)
• India
27 Mar 09
I missed the discussion otherwise I would have been the first to give correct answer.
Let's see
there are 7 girls with 7 backpack
i.e 49 backpack
Every backpack has 7 big cats
i.e 49*7=343 big cats.
Every big cats has 7 small cats:
i.e. 343*7=2401
Now total number of cats = 2401+343 = 2744
total cat legs = 2744*4 = 10976!
Are gilr's legs also count in to the answer?
Then the answer would be 10976+14=10990
So, 10976 or 10990 would be the answer!
1 person likes this
@ahgong (10064)
• Singapore
2 Apr 09
Well, at least you got it right at the first attempt.
And yes, we are counting the all the legs. Cats, kittens as well as girl's legs.
I have posted a pictorial version of the answer in my blog.
Do go and check it out!
The other way is to check out this picture I posted on mylot.
http://www.mylot.com/w/image/2167467.aspx
1 person likes this
I am not 
@Ysabel (1201)
• Philippines
25 Mar 09
this is a nice one, ahgong! i will give it a try though...
7 girls x 2 = 14 legs
7 big cats x 4 = 28 legs
7 little cats x 4 = 28 legs
14 legs + 28 legs + 28 legs = 70 legs.
total of 70 legs.
i'm wondering why there has to be computation for the backpacks from other mylotters. no offense meant.. i might be wrong too. backpacks... they don't have legs right? or do i have a different kind of backpacks on my mind????
am i correct, ahgong? ohh.. i have to wait until the 30th! he he
1 person likes this
@tipay26 (867)
• Philippines
25 Mar 09
hi ysabel,that's my answer too! the number of legs was asked not the number of backpacks...here's my computation:
7 girls x 2(leg per girl) = 14 human legs
7 big cats x 4 (leg per cat)=28 big cat legs
7 little cats x 4(leg per little cat)28 little cat legs
so...i'll add the human leg plus the little cat legs plus the big cats leg:
14+28+28= 70 legs... i did not include the 7 backpacks because backpacks do not have legs..
@scheng1 (24649)
• Singapore
25 Mar 09
haha, this is a tough question for adults, and a troublesome question for kids. They will have to multiply and multiply to get the answer.
Try to do the 2 questions below. This is one of the questions in the national examination for 11 years old kids in Singapore.
"Desmond had 480 more oranges than pears. After selling half of his oranges and half of his pears, he had four times as many oranges as pears left. Find the number of pears he had at first."
"Andy has $200 more than Peter. Andy gives 60% of his money to Peter. Peter then gives 25% of his money to Andy. In the end, Peter has $200 more than Andy. How much did Andy have at first?"
The 2 questions are listed at http://homeschoolmath.blogspot.com/2008/08/bar-diagram-problem.html
This maths teacher had a hard time solving the problems too.
1 person likes this
And these are for primary school kids?
Like dealing with a lot of algebra leh!@scheng1 (24649)
• Singapore
25 Mar 09
Yes, for primary school kids. At that level, they do not learn algebra, so please do not solve the problem by algebra.
They are supposed to draw models and use the charts or bars to solve the problem.
Most kids can get it right, it's the parents who got it wrong. Think most of us will fail the primary school examination questions.
1 person likes this
@jannike (8)
•
25 Mar 09
I got it in a minute or so. I think most people didn't consider the way the question was worded very well. There aren't 7 backpacks to start with (there are 49, because each of the 7 girls has 7, not 1, backpack), which is where most people went wrong in their calculations.
1 person likes this
@ahgong (10064)
• Singapore
26 Mar 09
Yeah... that is exactly what happened.
The way the question is worded, it played on the way we perceive the question.
That is why a lot of us got it wrong in the first attempt.
Maybe for a fifth grader, they do not have this preconceive notion about things, they tend to assume less, they may have gotten the answer faster.
Very good insight into the workings of the mind of an adult and a child eh?
Very good insight into the workings of the mind of an adult and a child eh? @sceptile_ex (97)
•
25 Mar 09
Hi, I think not because they don't know there are 49 backpacks but they assume it will not affected the calculation. When doing a Math question, most people tend to just pick out the keywords which they think is relevant without reading the whole context. So when the question said how many legs are there in the bus, they will think backpacks does not have leg, so this sentence can be ignored.
Same thing happen to those who got 72 legs, because they just pick out the 7 girls, 7 cats and 7 kittens from the sentences.
1 person likes this
@ahgong (10064)
• Singapore
2 Apr 09
ha ha ha ha ha... using the calculator is one thing. Getting the mechanics of the problem correct is the other.
I have posted the answer in my blog. As well as a picture to illustrate my point. Do go and check it out!
The other way is to check out this picture I posted on mylot.
http://www.mylot.com/w/image/2167467.aspx
@longbangod (1785)
• Philippines
25 Mar 09
This is a very interesting question. No wonder a lot of mylot members replied. Honestly it made my head ache a little so I stop to think aout the right answer. I just read some of the replies and there I saw the right answer. This is really nice!
1 person likes this
@ahgong (10064)
• Singapore
26 Mar 09
Yeah... it is fun to try the problem!
And after you see the answer, it makes the question look so simple right?
Yet when you first encountered it, it looks really tough!
Amazing how a few little words and a perception/assumption can make a simple thing look complicated, right?
@ahgong (10064)
• Singapore
2 Apr 09
Well, I have posted the answer and the workings. As well as a picture to illustrate my point.
They can be found in the latest entry in my blog!
Do go and check it out!
The other way is to check out this picture I posted on mylot.
http://www.mylot.com/w/image/2167467.aspx
Do go and check it out!
The other way is to check out this picture I posted on mylot.
http://www.mylot.com/w/image/2167467.aspx
@sceptile_ex (97)
•
25 Mar 09
Not commenting about your answer, but 14+28+28=70 and not 60.
1 person likes this
@sxrxnrr45601 (1171)
• United States
26 Mar 09
my guess would be 453 legs in all not including a bus driver lol
7x2=14 girls
there are 49 big cats so that would be 49x4=96
there are 7 little cats for every big cat so that would be 7x49=343
so it would be 343+14+96=453!
1 person likes this
@shashiverma555 (4)
• India
25 Mar 09
for the girls--7*2=14
for the big cats--- 7*7*7*4=1372
for the small cats--7*7*7*7*4=9604
total = 14+1372+9604=10990
is it correct.....
1 person likes this
@phoenix79 (302)
• United States
25 Mar 09
lets break this down
Seven girls would have 14 legs
seven kitten for seven cats 49 kitten
seven * 4= 28
49* 4 106 legs in all
1 person likes this
@phoenix79 (302)
• United States
25 Mar 09
oh there are seven book bags
times by 7
742
1 person likes this
