23 people are there, they are shaking hands together, How many handshakes…
2025
23 people are there, they are shaking hands together, How many handshakes possible?
- A.
250
- B.
252
- C.
242
- D.
253
Attempted by 54 students.
Show answer & explanation
Correct answer: D
Key formula: For n people, the number of unique handshakes is n(n−1)/2.
Step 1: Each person can shake hands with 22 others, so counting per person gives 23 × 22 = 506.
Step 2: Each handshake is counted twice when we multiply per person (A with B and B with A), so divide by 2: 506/2 = 253.
Alternate using combinations: choose any 2 people out of 23, which is 23 choose 2 = 23×22/2 = 253.
Answer: 253