Answer:
0.2734
Step-by-step explanation:
Using the binomial probability relation :
P of success, p = 1/2 ; q = 1 - p = 0.5
Number of trials, n = 7
Number of successful outcomes = 4
Recall:
P(x = x) = nCx * p^x * q^(n-x)
P(x = 4) = 7C4 * 0.5^4 * 0.5^3
P(x = 4) = 35 * 0.5^4 * 0.5^3
P(x = 4) = 0.2734
Probability of obtaining 4 heads = 0.2734
