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A coin is tossed twice, what is the probability that at least one tail occurs?

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Question

A coin is tossed twice, what is the probability that at least one tail occurs?

Sum
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Solution

Sample space of the given experiment

S = {HH, HT, TH, TT}

∴ Total number of possible outcomes = 4 at least

Ways of getting a tail TH, HT, TT = 3

Probability of getting at least 1 tail by tossing a coin twice = `3/4`

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Chapter 14: Probability - EXERCISE 14.2 [Page 305]

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NCERT Mathematics [English] Class 11
Chapter 14 Probability
EXERCISE 14.2 | Q 2. | Page 305

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