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Re: What is the probability of tossing a coin five times and having heads
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04 Nov 2019, 01:20
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Formula: Probability of getting r heads when coin is tossed n times = nCr*\(p^r*q^{n-r}\) Where p = probability of getting heads & q = probability of getting tails
Probability(at least 2 heads) = 1 - Probability(0 heads or 1 head)
Probability (0 heads) = \(5C_0*(1/2)^5 = 1/32\) Probability (1 head) = \(5C_1*(1/2)^5 = 5/32\)
Re: What is the probability of tossing a coin five times and having heads
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04 Nov 2019, 04:58
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For a head to appear at least two times, we have 5C2 + 5C3 + 5C4 + 5C5 = 10+10+5+1=26 total possibilities Total events = 2^5 = 32 P(at least 2H) = 26/32 = 13/16.
1. total possibilities of HHTTT: 5! / (2! x 3!) = 10 nos 2. total possibilities of HHHTT: 5! / (3! x 2!) = 10 nos 3. total possibilities of HHHHT: 5! / (4! x 1!) = 5 nos 4. total possibilities of HHHHH: 5! / (5! x 0!) = 1 nos
=> total possibilities of minimum 2 heads = 10+10+5+1 = 26 nos
=> P ( min. 2 heads) = favourable outcomes / total outcomes = 26/32 = 13/16
Re: What is the probability of tossing a coin five times and having heads
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04 Nov 2019, 13:03
First we count What is the probability that the coin lands on the head for one time and a never apeares on head. (1/2)⁴ × 1/2=1/32 (1/2)^5=1/32 1- 2/32 =30/32=15/16