Question

The State of Nevada has seatbelt laws for drivers. It is known that 68 % of the drivers wear seatbelts. A sample of six drivers is selected.The average number of people you should expect to find wearing their seatbelt is

A. 4.08
B. 3.34
C. 6.68
D. 4.26

Answer 1

A . 4.08

The average number of people you should expect to find wearing their seat belt is

μ= n p = 4.08

Explanation:

Step(i):-

Given the probability that drivers wear seat belts

p = 68% =0.68

Given sample size 'n' =6

we will use binomial distribution

mean of the binomial distribution μ= n p

step(ii):-

The average (0 r) mean of the binomial distribution

μ= n p = 6 X 0.68 = 4.08

The standard deviation of the binomial distribution

σ = √npq

=
`√(6 X 0.68 X 0.32) = 1.142`

Final answer:-

The average number of people you should expect to find wearing their seat belt is

μ = 4.08

The standard deviation of the people you should expect to find wearing their seat belt is

σ = 1.142