abhasjha wrote: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
P(H on the 1st flip) = 1/2.
P(H on the 2nd flip) = 1/2.
P(H on the 3rd flip) = 1/2.
P(T on the 4th flip) = 1/2.
P(T on the 5th flip) = 1/2.
Since we want all of these events to happen, we multiply the fractions:
1/2 * 1/2 * 1/2 * 1/2 * 1/2 = 1/32.
The correct answer is
E.
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