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A compound experiment consists of tossing a coin, drawing a letter at random from the alphabet, and then tossing two coins. What is the probability of getting a tail, the letter T, and then two tails?

User MuratOzkan
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2 Answers

3 votes
The answer should be "1/208"
User Talguy
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4 votes
We should each take these probabilities first individually.
Probability of tails in a coin toss = 1/2
Probability of drawing letter T from the alphabet = 1/26
Probability of 2 tails in 2 coin toss = 1/4
Sample space = {HH, TT, HT, TH}

Add these together since these events happen after another = 1/2 + 1/26 / + 1/4 = 41/52

The final probability is 41/52
User Zenon
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