Jason remembers nine digits of a ten digit phone number. He remembers that the last digit is an even number. If he guesses that last digit, what is the probability that he dials the correct number?
My answer: 1/5 probability
4 answers
why 1/5? 5 of the 10 digits are even.
how do I do it then?
fyi this is actually right
Assuming 0 counts as an even digit, then the last digit must be 2, 4, 6, 8, 0 = 5 options
Only one of these is the correct one
Therefore the probability that he dials correctly = 1/5 or 0.20 or 20%
Assuming 0 counts as an even digit, then the last digit must be 2, 4, 6, 8, 0 = 5 options
Only one of these is the correct one
Therefore the probability that he dials correctly = 1/5 or 0.20 or 20%
My bad. You are correct.