At Holy Rosary Elementary the probability that any one stud

. At Holy Rosary Elementary, the probability that any one student has contracted Ebola is 2%. Each class has 20 students. The school nurse inspects all 20 students in each of 6 classes. What is the probability that in exactly 2 classes, more than one student has contracted Ebola?

Solution

The probability that any one student has contracted Ebola is 0.02.

Each class has 20 students. The school nurse inspects all 20 students in each of 6 classes.

Thus, the probability that in exactly 2 classes, more than one student has contracted Ebola is:

1-P(X=1)

=1-20C6*0.02^6*0.98^14

=0.000001