Question

If you make random guesses for 6 multiple-choice test questions (each with five possinle answers), what is the probability of getting the final question correct given the first five answers are all wrong?

Answer 1

What happened in the first questions doesn't influence the final question, so the probability is simply 1/5 = 0.2

Answer 2

39.31 percent

use binomial Cdf on your calculator.

insert it like such:

num trials: 6

prob: .2

Lower bound: 1

Lower bound: 2

then click enter :)