1. A local community college determines the probability that a student will reenroll for a second year is 0.91. A representative surveys 100 random first year students and asks them if they will be enrolling for the next year. What is the probability that exactly 91 of them will enroll?

Question

a. 0.138
b. 1.000
c. 0.910 <--my answer
d. 0.276

Answer 1

C(100,91) (.91)^91 (.09)^9
= .138106...

The hard part was to evaluate C(100,91)
If you use the build-in function _n C _r ,
your calculator will overload and you get an error message.
that is because the largest number most calculators can store is 96!
so you have to do C(100,91)
= 100x99x98x97x96x95x94x93x92/9!

Answer 2

I meant to say:

that is because the largest number most calculators can store is 69!

This had no effect on my conclusion or answer.