Question

In a conference of 8 persons, if each person shake hand with the other one only, then the total number of shake hands shall be

• A. 64
• B. 56
• C. 49
• D. 28

Answer 1

Answer: (D)

28

Answer 2

Total number of shake hands when each person shake hands with the other once only = $8C_{2} = 28$ ways.