If a certain coin is flipped, the probability that the coin will land heads is 1/2. If the coin is flipped 5 times, what is the probability that it will land heads up on the first 3 flips and not on the last 2 flips?
A. 3/5
B. 1/2
C. 1/5
D. 1/8
E. 1/32
OA E
Source: GMAT Prep
If a certain coin is flipped, the probability that the coin will land heads is 1/2. If the coin is flipped 5 times, what
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The question is asking for the probability of a set of outcomes which occur in a specific order.
Since each toss is independent of the other and each face has a 1/2 chance of appearing the probability is [spoiler]1/32, E[/spoiler]
If the question had asked for probability of 3 heads and 2 tails occurring in 5 tosses, then would need to consider all orders that produce the result
Since each toss is independent of the other and each face has a 1/2 chance of appearing the probability is [spoiler]1/32, E[/spoiler]
If the question had asked for probability of 3 heads and 2 tails occurring in 5 tosses, then would need to consider all orders that produce the result
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We want P(heads on 1st AND heads on 2nd AND heads on 3rd AND tails on 4th AND tails on 5th)BTGmoderatorDC wrote: ↑Sat Jun 18, 2022 10:58 pmIf a certain coin is flipped, the probability that the coin will land heads is 1/2. If the coin is flipped 5 times, what is the probability that it will land heads up on the first 3 flips and not on the last 2 flips?
A. 3/5
B. 1/2
C. 1/5
D. 1/8
E. 1/32
OA E
Source: GMAT Prep
= P(heads on 1st) x P(heads on 2nd) x P(heads on 3rd) x P(tails on 4th) x P(tails on 5th)
= 1/2 x 1/2 x 1/2 x 1/2 x 1/2
= 1/32
Answer: E
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 Scott@TargetTestPrep
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The probability that the first 3 flips are heads and last 2 flips are tails is:BTGmoderatorDC wrote: ↑Sat Jun 18, 2022 10:58 pmIf a certain coin is flipped, the probability that the coin will land heads is 1/2. If the coin is flipped 5 times, what is the probability that it will land heads up on the first 3 flips and not on the last 2 flips?
A. 3/5
B. 1/2
C. 1/5
D. 1/8
E. 1/32
OA E
Source: GMAT Prep
P(HHHTT) = (1/2)^5 = 1/32.
Answer: E