In: Statistics and Probability
Probability that a given person has been in a car accident, p = 12% = 0.12
The given sample size n = 151
Let X be the number of people have been in a car accident out of 151 people. Then X ~ Binomial(n = 151, p = 0.12)
Mean = np = 151 * 0.12 = 18.12
Standard deviation = = 3.993194
Assuming normal approximation to binomial distribution,
P(X < 16) = P(X < 15.5) (Using continuity correction)
= P[Z < (15.5 - 18.12) / 3.993194]
= P[Z < -0.6561]
= 0.2559