Statistics and R

Question

A federal report found that a lie detector test given to someone telling the truth will suggest that they lied in about 20% of cases. A company asks the 12 job applicants for a new position about thefts from previous employers.

(a) What is the probability that the lie detector indicates that at least one of the applicants is lying?

liars<- 1-pbinom(0, size = 12, prob= 0.2) I understand on how to do this but dont understand how to use it part b!

(b) Create a vector of appropriate values that would be used as the input to determine the probability of at least one through the probability of all twelve are indicated to be lying. Use this vector as the input of the appropriate probability function and save the resulting probabilities rounded to three decimal places.

Answer 1

The first value in binom can be a vector. Thus, our answer would be

round(1 -pbinom(0:11,12,.2),3)

Note that you would get the same result with round(pbinom(11:0,12,.8),3)