Probability question.

Question

When tetanus affects new born infants,it has been observed that only 10% recover in a random sample of 5 new borne affected by tetanus. What is the probability that: 1. Only 2 of them recovers. 2. at most 3 recovered 3. At least one.

Answer 1

binomialpdf(5,.1,2)=.0729

binomialcdf(5,.1,3)= .99954

1-binomialcdf(5,.1,0)=.40951