In a room, there are 10 people. Each person shakes hands with every other person exactly once. How many handshakes occur in total?
Category: Brain Teasers · Difficulty: expert
Hint: Think about combinations and how many unique pairs can be formed.
Answer
45 handshakes
Explanation
The formula for handshakes among n people is n(n-1)/2. For 10 people, it’s 10(9)/2 = 45.
This is a expert brain teasers riddle — one of the harder riddles here. The answer is 45 handshakes.
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