Question

Fifty-three percent of all people in the U.S. have at least some college education. If 20 people are randomly selected find the probability that at least 6 have some college education.

a) 0.9712

b) 0.9887

c) 0.903

d) 0.3218

Answer 1

X : number of people have some college education.

X ~ bin (n,p)

where, n = 20

p = 53% =0.53

q = (1-p ) =(1-0.53 )= 0.47

the pmf of the distribution be:-

the probability that at least 6 have some college education is :-

( i have rounded off all the values to 4 decimal places )

[ this is the nearest value among all the four options ]

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