Answer: 0.3125
As a fraction, 0.3125 = 5/16
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Work Shown:
n = 5 trials
p = 0.5 is the probability of landing tails
x = 3 = number of tails we want to happen
Use the binomial PDF formula to get
(n C x)*(p)^x*(1-p)^(n-x)
(5 C 3)*(0.5)^3*(1-0.5)^(5-3)
10*(0.5)^3*(0.5)^(2)
0.3125
note: flipping a single coin 5 times is the same as flipping 5 independent coins one time
