At a party, everyone shook hands with everybody else. There
were 66 handshakes. How many people were at the party?
10
11
12
13
Answer Posted / geeyemaar
consider n be the no of people in the party,let us give the combination for those handshakes.for that,
nc2 = 66
n(n-1)/2 = 66
n(n-1) = 132
sq(n)-n = 132
sq(n)-n-132 = 0
sq(n)-12n+11n-132 = 0
(n-12)(n+11) = 0
n = 12,-11,
taking the positive value we get the answer as 12 Handshakes
| Is This Answer Correct ? | 36 Yes | 5 No |
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