Question

12 members were present at a board meeting. Each member shook hands with all of the other members before & after the meeting.How manyhand shakes were there?

Answer 1

Answer:

66

Step-by-step explanation:

Dude its very easy...just follow my steps...

Using ' ! ' as Factorial sign as the usual one is not available on p.c.

Total members = 12

Total members = 12Persons shake hands at a time = 2

Hence,

Total handshakes =

${}^{12} c2$

(12 choose 2) as Combination

$= \frac{12 !}{ 2! \times (12 - 10) !}$

$= \frac{ 10! \times 11 \times 12}{ 2! \times 10 ! }$

$= 11 \times 6$

$= 66$

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