that is the number for all correct (or incorrect)
see the answer to your other posted question
A true-false test consists of 15 items.
(a) If Chris does not study at all and guesses each and every item in the test, describe the probability model for the number of correct guesses.
each individual question has a probability of 1/2 of being correct
so you want (1/2)(1/2) .... (1/2) --- (15 times)
= (1/2)^15
= 3.051757813x-0.5
is that correct ?
1 answer