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36 votes
What is the probability of flipping a coin 7 times and getting heads 4 times?Round your answer to the nearest tenth of a percent.A. 27.3%B. 0.8%C. 5.5%D. 16.4%

User Octo Poulos
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2.1k points

1 Answer

10 votes
10 votes

We know that

• The probability of a head is 1/2.

,

• The probability of a tail is 1/2.

Notice that the number of times they flip a coin is 7. Since both probabilities are the same, we just have to multiply 1/2 seven times by itself.


P=((1)/(2))^7

Now, we multiply the probability with 7 since there are 7 possibilities.


P=7\cdot((1)/(2))^7=7(0.0078125)=0.0546\approx0.055

Then, we multiply by 100 to express it as a percentage.


0.055\cdot100=5.5

Therefore, the answer is C. 5.5%.

User Ronald McBean
by
2.9k points
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