Question

Suppose that n = 100 and p = 0.5 for a binomial experiment. Find the P(x > 50) A. 0.5398 B. 0.6179 C. 0.4602 D. 0.3821 E. None of these

Answer 1

we have that

P(x>50)=P(x=51)+P(x=52)+P(x=53)+.....P(x=100)

so

$P(x=51)=\frac{100!}{51!(100-51)!}*0.5^{(51)}*0.5^{(49)}$

P(x=51)=0.0780