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#1 2006-03-01 04:14:14

ganesh
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Registered: 2005-06-28
Posts: 12,924

Set Language

SL # 1

In a school, it is found that 100 students play cricket, 70 play hockey, 60 play basketball, 41 play cricket and hockey, 33 play basketball and hockey and 27 play basketball and cricket. In total, 140 students play either one of more of these three games. Find the number of students who play all the three games.


Character is who you are when no one is looking.

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#2 2006-03-01 04:36:30

espeon
Real Member
Registered: 2006-02-05
Posts: 2,586

Re: Set Language

11?


Presenting the Prinny dance.
Take this dood! Huh doood!!! HUH DOOOOD!?!? DOOD HUH!!!!!! DOOOOOOOOOOOOOOOOOOOOOOOOOD!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

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#3 2006-03-01 05:10:48

krassi_holmz
Real Member
Registered: 2005-12-02
Posts: 1,908

Re: Set Language

Correct!!!
How did you get this?

I got it with a system.


IPBLE:  Increasing Performance By Lowering Expectations.

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#4 2006-03-01 16:04:17

ganesh
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Registered: 2005-06-28
Posts: 12,924

Re: Set Language

Excellent, espeon and krassi_holmz! smile


Character is who you are when no one is looking.

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#5 2006-03-10 16:16:07

ganesh
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Registered: 2005-06-28
Posts: 12,924

Re: Set Language

SL # 2

In a survey of 100 computer professionals, it was found that 48
read 'Byte', 39 read 'PC World' and 44 read 'PC Magazine'. It was also found that 17 read both Byte and PC World, 18 read both PC World and PC Magazine and 22 read both Byte and PC Magazine and the balance 20 read none of these 3 magazines. Determine the number of professionals who read exactly one magazine.


Character is who you are when no one is looking.

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#6 2006-03-10 16:29:23

Ricky
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Registered: 2005-12-04
Posts: 3,791

Re: Set Language


"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

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#7 2006-03-10 16:32:49

ganesh
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Registered: 2005-06-28
Posts: 12,924

Re: Set Language

Try again, Ricky!


Character is who you are when no one is looking.

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#8 2006-03-10 17:13:37

Ricky
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Registered: 2005-12-04
Posts: 3,791

Re: Set Language

Ah, I missed the last part about the 20.  That makes it:


"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

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#9 2006-03-10 17:30:54

ganesh
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Registered: 2005-06-28
Posts: 12,924

Re: Set Language

I get a different answer, Ricky!


Character is who you are when no one is looking.

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#10 2006-03-10 18:31:27

ganesh
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Registered: 2005-06-28
Posts: 12,924

Re: Set Language

This is how I solved the problem:-

n(A U B U C) =
n(A) + n(B) + n(C) - n(AnB) - n(BnC) - n(AnC) + n(AnBnC)

Here, n(A U B U C) = 100-20 = 80
n(A) = 48, n(B) = 39, n(C)=44,
n(AnB)=17, n(BnC)=18, n(AnC)=22, n(AnBnC)=?.
Therefore, 80 = 48+39+44-17-18-22+n(AnBnC)
Therefore, n(AnBnC)=6.
Only A = 48-17-22+6 = 15
Only B = 39-17-18+6=10
Only C = 44-18-22+6=10.
Therefore, the number of professionals who read only one magazine is 15+10+10=35.


Character is who you are when no one is looking.

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#11 2008-08-05 14:11:09

Sudeep
Member
Registered: 2008-07-21
Posts: 20

Re: Set Language

In a survey of political preference,78% of those asked were in favoured of at least one of the proposals: I, II and III. 50% of those asked favored proposal III. If 50% of those asked favoured all three of the proposals, what percentage of those asked favoured more than one of the 3 proposals.

Give explaination of your approach with your answer

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#12 2008-08-28 20:08:12

Sudeep
Member
Registered: 2008-07-21
Posts: 20

Re: Set Language

In a survey of 200 students of a higher secondary school, it was found that 120 studied mathematics; 90 studied physics; 70 studied chemistry; 40 studied mathematics and physics; 30 studied physics and chemistry; 50 studied chemistry and mathematics, and 20 studied none of these subjects. Find the number of students who studied all the three subjects?

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#13 2008-08-28 20:21:04

Sudeep
Member
Registered: 2008-07-21
Posts: 20

Re: Set Language

In a survey of 100 persons it was found that 39 subscribed to TV Guide, 26 subscribed to Time and 6 subscribed to Scientific American. A total of 15 subscribed to at least two of these magazines and 2 subscribed to all three. How many persons did not subscribe to any of the three?

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#14 2008-08-29 02:58:41

TheDude
Member
Registered: 2007-10-23
Posts: 361

Re: Set Language


Wrap it in bacon

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#15 2011-07-15 05:00:07

prithvi3459
Member
Registered: 2011-07-15
Posts: 2

Re: Set Language

ganesh wrote:

SL # 1

In a school, it is found that 100 students play cricket, 70 play hockey, 60 play basketball, 41 play cricket and hockey, 33 play basketball and hockey and 27 play basketball and cricket. In total, 140 students play either one of more of these three games. Find the number of students who play all the three games.

39 nos

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#16 2011-07-15 16:41:23

ganesh
Moderator
Registered: 2005-06-28
Posts: 12,924

Re: Set Language

Hi prithvi3459,

The answer is 11.

140 = 100 + 70 + 60 - 41 - 33 - 27 + x
x = 11


Character is who you are when no one is looking.

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#17 2011-09-05 12:39:20

Stormtangent
Member
Registered: 2011-09-03
Posts: 33

Re: Set Language

Last edited by Stormtangent (2011-09-05 12:40:04)


"Have you ever had a dream that you were so sure was real? What if you were unable to wake from that dream? How would you know the difference between the dream world and the real world? "

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#18 2011-09-05 12:45:40

Stormtangent
Member
Registered: 2011-09-03
Posts: 33

Re: Set Language


"Have you ever had a dream that you were so sure was real? What if you were unable to wake from that dream? How would you know the difference between the dream world and the real world? "

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#19 2011-09-05 17:12:47

ganesh
Moderator
Registered: 2005-06-28
Posts: 12,924

Re: Set Language

Hi Stormtangent,

The solutions #1 and #2 are correct. Excellent!


Character is who you are when no one is looking.

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