What is the probability of getting three heads in a row and

swerve wrote:What is the probability of getting three heads in a row and then a tail on four flips of a coin?

A. \(\frac{1}{16}\)

B. \(\frac{2}{16}\)

C. \(\frac{3}{16}\)

D. \(\frac{4}{16}\)

E. \(\frac{5}{16}\)

The OA is A

Source: Veritas Prep

For an unbiased coin, upon flipping a coin

probability of getting a head = 1/2; and
probability of getting a tail = 1/2

Probability of getting 3 heads in a row = 1/2 * 1/2 * 1/2 = 1/8; and
Probability of getting a tail in the 4th flip = 1/2

Thus, the probability of getting three heads in a row and then a tail on four flips of a coin = 1/8 * 1/2 = 1/16

The correct answer: A

Hope this helps!

-Jay
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swerve wrote:What is the probability of getting three heads in a row and then a tail on four flips of a coin?

A. \(\frac{1}{16}\)

B. \(\frac{2}{16}\)

C. \(\frac{3}{16}\)

D. \(\frac{4}{16}\)

E. \(\frac{5}{16}\)

The OA is A

Source: Veritas Prep

We need to determine P(HHHT).

Notice that there are 2^4 = 16 total outcomes in four flips of a coin and HHHT is one of the outcomes; therefore P(HHHT) = 1/16.

Answer: A