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Question
I toss three coins together. The possible outcomes are no heads, 1 head, 2 heads and 3 heads. So, I say that probability of no heads is `1/4`. What is wrong with this conclusion?
Solution
I toss three coins together ...[Given]
So, total number of outcomes = 23 = 8
And possible outcomes are (HHH), (HTT), (THT), (TTH), (HHT), (THH), (HIH) and (TTT)
Now, probability of getting no head = `1/8`
Hence, the given conclusion is wrong because the probability of no head is `1/8` not `1/4`.
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