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by ukr.net » Mon Dec 03, 2007 5:19 am
If 10 persons meet at a reunion and each person shakes hands exactly once with each of the others, what is the total number of handshakes?

10•9•8•7•6•5•4•3•2•1
10•10
10•9
45
36

ANS is D . How to solve???
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by ri2007 » Mon Dec 03, 2007 5:42 am
Think as this as how many pairs can u make with 10

so ans is 10 C 2 = 45
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by sujaysolanki » Mon Dec 03, 2007 5:44 am
10C2=!10/!8*!2=45

or just add them 9+8+7+6+5+4+3+2+1=45
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by II » Tue Dec 25, 2007 5:19 am
ri2007 wrote:Think as this as how many pairs can u make with 10

so ans is 10 C 2 = 45
Sorry for the basic question ... but what do you mean by the "C" ... "10 C 2" ... what is the C ?

thanks.
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by camitava » Tue Dec 25, 2007 10:42 pm
II, the word - C - used by ri2007 stands for Combination. This is a math function or concept u can say! For more information, refer the following link -
Correct me If I am wrong


Regards,

Amitava
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