Question

A group of ten students shake hands one another among themselves What is the total number of shaking of hands?
(A) 20
(B) 56
(C) 45
(D) 90

Answer 1

Answer: (c) 45

Explanation:

Answer 2

The total number of shaking of hands is (C) 45.

For n number of students, number of hands shaken will be (n-1).

Now multiplying them will count these handshakes as twice, thus divide by 2.

Therefore , formula will be n(n-1)/2.

The total number of shaking of hands =10(10-1)/2.

The total number of shaking of hands =10*9/2.

The total number of shaking of hands =90/2.

Thus, the answer is 45.