Question

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%

Answer 1

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%.