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Six coins are tossed at the same time 64 times. If getting a head is taken as a success, what is the expected number of times that there will be at least 3 successes?
- 64
- 21
- 32
- 42
Correct answer: 42
Solution
The expected number of times to get at least 3 heads when tossing 6 coins follows a binomial distribution. The probability of getting at least 3 heads in one toss is calculated, and multiplying this probability by the number of trials (64) yields the expected value, which is 42.
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