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A coin toss bet is placed between two friends such that the person who wins four tosses first is the winner. What is the total number of possible ways in which the bet can play out

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Answer:

who wins four tosses first is the winner.

possible cases-7 tosses, 6 tosses, 5 tosses, 4 tosses

We get cases of Win of Head first-4 tosses

All 4 must be Head

Number of ways = 1

5 tosses-5th must be Head

there are 3 Head out of 4 in ⁴C₃ = 4 Ways

6 tosses-6th must be Head

there are 3 Head out of 5 in ⁵C₃ = 10 Ways

7 tosses-7th must be Head

there are 3 Head out of 6 in ⁶C₃ = 20 Ways

Cases of Head wins = 1+ 4 + 10 + 20 = 35

similarly cases when Tails Wins = 35

Total Possible cases = 35 + 35 = 70

70 is total number of possible ways in which the bet can play out.

Explanation:

I hope that this helps u out..

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