Algebra

sathyaram's Avatar
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28 Mar 2012 13:11:09 IST
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P and C
Engineering Entrance , JEE Main , JEE Main & Advanced , Mathematics , Algebra

  A total of 28 handshakes was exchanged at the conclusion of a party. Assuming that each participant was equally polite toward all the others, the number of people present was: 

\textbf{(A)}\ 14 \qquad\textbf{(B)}\ 28 \qquad\textbf{(C)}\ 56 \qquad\textbf{(D)}\ 8 \qquad\textbf{(E)}\ 7



Comments (8)


Blazing goIITian

Joined: 21 Mar 2012
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28 Mar 2012 13:15:28 IST
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a total of how many handshake

Hot goIITian

Joined: 10 Oct 2011
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28 Mar 2012 13:17:40 IST
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option D answer is 8 

 

 


Blazing goIITian

Joined: 21 Mar 2012
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28 Mar 2012 13:25:58 IST
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i cant see the whole question even not option will u write it again

Hot goIITian

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28 Mar 2012 13:33:05 IST
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hello tarun click answer on the right side bottom of the question then you can see the question  my friend :)

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28 Mar 2012 13:51:01 IST
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 @ Srini: Ur right machan !

 

edison's Avatar

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28 Mar 2012 14:15:02 IST
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 If the number of people are 'n' then

 

number of handshakes = (n-1) + (n-2) + (n-3)+ ...+1

 

or number of handshakes = n(n-1)/2

 

here number of handshakes = 28

 

So, n(n-1) / 2 = 28 on solving gives

 

n = 7

sathyaram's Avatar

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28 Mar 2012 17:54:18 IST
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@ edison sir: Sir,uve made an mistake in the last step sir...n=8 actually...
sudhindra shenoy's Avatar

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29 Mar 2012 21:45:34 IST
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 yeah its 8




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