Question

What is the probability of flipping a coin 7 times and getting heads 6 times? Round your answer to the nearest tenth of a percent.
A. 16.4%
B. 5.5%
C. 27.3%
D. 0.8%

Answer 1

Answer:

B. 5.5%

Step-by-step explanation:

For a fair coin,

Probability of a head, P(H) = 1/2 = 0.5

Probability of a tail , P(T) = 1/2 = 0.5

The number of possible outcomes is small enough to simply list the outcome:

The possible outcomes of flipping a coin 7 times and getting heads 6 times are these 7 possibilities:

THHHHHH

HTHHHHH

HHTHHHH

HHHTHHH

HHHHTHH

HHHHHTH

HHHHHHT

The probability of EACH of the above outcomes is

= (0.5)(0.5)(0.5)(0.5)(0.5)(0.5)(0.5)

= (0.5)⁷

Since there are 7 possibilities and since the probabilities of every outcome is identical, the probability of rolling the 7 outcomes is,

= 7 x probability of each outcome

= 7 x (0.5)⁷

= 0.5468

= 5.468%

= 5.5% (nearest tenth)

Answer 2

The answer for this would be C.