12 man participate in work Recruitment Service. Each participant saw every other participant and shook his hand.
How many handshakes took place?
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This is just math...
The numbers each represent a person. When we move on to person 2, he does not shake 11 times. He'll shake 10, due to already shaking with 1 earlier. This will repeat, which makes the equation super simple:
(0 because by the time it's 12's turn he's shaken with everyone already)
Which comes out to be:
66 handshakes will go down between those 12 men. 78 if people shake their own hands (lol)
This one is easy.
Each person needs to shake hands with 11 other participants and the total number of participants are 12. So the total number handshakes that took place would be
But then there are some people who have shook their hands twice! So just divide the answer by 2 thus giving us
and that is the answer. This is done because the first participant shakes their hand with 11 other participants,the second participant shakes their hand with 10 other participant(-1 because he has already shook hands with the first participant) and so on.. Thus the answer is
+0 in the answer is because the last participant has already shook his hands with all the other participant and so he does not have to shake hands with anyone.