John tossed a fair coin 3 times. What is the probability that the outcome was “tails” exactly twice?
A. 1/8
B. 1/4
C. 3/8
D. 1/2
E. 9/10
OA C
Source: EMPOWERgmat
John tossed a fair coin 3 times. What is the probability that the outcome was “tails” exactly twice?
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John tossed a fair coin 3 times. What is the probability that the outcome was “tails” exactly twice?
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We need to determine the following:BTGmoderatorDC wrote: ↑Tue Feb 21, 2023 5:18 pmJohn tossed a fair coin 3 times. What is the probability that the outcome was “tails” exactly twice?
A. 1/8
B. 1/4
C. 3/8
D. 1/2
E. 9/10
OA C
Source: EMPOWERgmat
P(TTH) = (1/2)^3 = 1/8
Since TTH can be arranged in 3!/2! = 3 ways, the probability is 3 x (1/8) = 3/8.
Answer: C
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