Connor flips a coin four times. if he can assume that heads occurs 50% of the time and tails occurs 50% of the time, what is the probability of at most 2 heads appearing?
Question
Answer:
The probability is 0.6875.We find the probability of 0 heads, 1 heads, and 2 heads:
[tex]_4C_0(0.5)^0(0.5)^4+_4C_1(0.5)^1(0.5)^3+_4C_2(0.5)^2(0.5)^2 \\ \\=\frac{4!}{4!0!}(0.5)^4+\frac{4!}{1!3!}(0.5)(0.5)^3+\frac{4!}{2!2!}(0.5)^2(0.5)^2 \\ \\=0.5^4+4(0.5)^4+6(0.5)^4=0.6875[/tex]
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11 months ago
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