Author Topic: Food for Brain - Maths puzzle  (Read 10615 times)

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xyz

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Food for Brain - Maths puzzle
« on: August 26, 2008, 05:51:40 AM »
A father gave his son Rs 20 and asked him to get three things; books that cost Rs 5 each, notebooks that cost Re 1 each and pencils that costs 25p each. He also told him that he will be rewarded if total number of books, notebooks and pencils will be 20 too.


hint-
[hide]
5x+1y+.25z=20
x+y+z = 20
[hide]

xyz

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Re: Food for Brain - Maths puzzle
« Reply #1 on: August 26, 2008, 05:54:36 AM »
You are about to leave for holiday, but you forgot socks! You race back to your room, but all the lights are off, so you can't see the color of the socks.

Never mind, because you remember that in your drawer there are ten pairs of white socks, ten pairs of black socks, and eleven pairs of blue socks, but they are all mixed up.

How many of your socks do you need to take before you can be sure to have at last one matching pair?


answers later.... try first

xyz

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Re: Food for Brain - Maths puzzle
« Reply #2 on: September 09, 2008, 04:18:01 AM »
Nobody interested ???

bailey.rein

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Re: Food for Brain - Maths puzzle
« Reply #3 on: December 11, 2008, 07:00:01 AM »
Oh, I'm sorry I'm not good in problem solving.

turboshiv

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Re: Food for Brain - Maths puzzle
« Reply #4 on: February 26, 2010, 12:18:26 AM »
4 socks

kurakani

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Re: Food for Brain - Maths puzzle
« Reply #5 on: February 26, 2010, 06:35:45 AM »
4 socks

yes

there are only three colors, so if you take four socks then you are guaranteed to have at least one matching pair.

kanchabooze

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Re: Food for Brain - Maths puzzle
« Reply #6 on: February 27, 2010, 07:24:49 PM »
5 ko 1, 1 ko 14 , .25 ko 4 = 20....milyo?...milena bhane ajjai hint deu la

tundikhel

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Re: Food for Brain - Maths puzzle
« Reply #7 on: April 16, 2010, 05:11:00 AM »
5 ko 1, 1 ko 14 , .25 ko 4 = 20....milyo?...milena bhane ajjai hint deu la

1+14+4 = 19

3 unknowns and only two equations -- not possible to solve by the equation
How about some trail and errors

Lets start with x=5, x=4
x=3 ..........Rs15
Y +0.25 Z =5

The answer should be 3 x, 1 y and 16 z.
3books = Rs.15
1notebook= Rs. 1
16pencils = Rs.4

20 items = Rs. 20

done!!

tundikhel

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Re: Food for Brain - Maths puzzle
« Reply #8 on: April 16, 2010, 05:18:15 AM »
My question

There is a bus with 7 kids inside.
Each kid has 7 bags.
Inside each bag there are 7 teddy bears.
Each teddy bears has 7 small small teddies.
All teddies have 4 legs each.
How many legs are on the bus?


helloall

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Re: Food for Brain - Maths puzzle
« Reply #9 on: April 16, 2010, 08:10:50 AM »
Legs of all teddies=7*7*7*7*4=9604
Legs of 7 kids and the driver=16
Therefore, total legs in the bus=9620
Done||