Question

Eight of the 50 digital video recorders (DVRs) in an inventory are known to be defective. What is the probability you randomly select an item that is not defective?

Answer 1

8 of the 50 digital video recorders are defective.

The probability to be defected if given by:

P(defected) = defected DVRs / Total of DVRs

Replacing:

P(defected) = 8/50

Now, the probability that the DVR is not defective is equal to:

P(not defective)= 1 -P(defected)

Replacing :

P(not defective)= 1-8/50

P(not defective)=0.84

Hence, the probability that randomly selected an item that is not defective is given by 0.84.