Mark the correct alternative in the following:

A box contains 100 pens of which 10 are defective. What is the probability that out of a sample of 5 pens drawn one by one with replacement at most one is defective?

Given:

Total pens=100

Defective pens=10

n=5

P(atmost one non-defective pen)=?

P(defective pens

=p

P(atmost one non-defective pen)=p(x<10)

=p(x=0)+p(x=1)

= ^{5}C_{0} p^{0} q^{5}+5pq^{4}

1