# Statistics MCQs –Continuous Distributions Part 12

Doorsteptutor material for NCO is prepared by world's top subject experts: fully solved questions with step-by-step explanation- practice your way to success.

221. A statistical analysis of long-distance telephone calls indicates that the length of these calls is normally distributed with a mean of 240 seconds and a standard deviation of 40 seconds. What is the length of a particular call (in seconds) if only 5% of calls are shorter?

a. 146.95

b. 157.85

c. 174.21

d. 333.05

e. 305.79

Answer: C

222. A statistical analysis of long-distance telephone calls indicates that the length of these calls is normally distributed with a mean of 240 seconds and a standard deviation of 40 seconds. What is the length of a particular call (in seconds) if only 1% of calls are longer?

a. 146.95

b. 157.85

c. 174.21

d. 333.05

e. 305.79

Answer: D

223. A statistical analysis of long-distance telephone calls indicates that the length of these calls is normally distributed with a mean of 240 seconds and a standard deviation of 40 seconds. What is the length of a particular call (in seconds) if only 5% of calls are longer?

a. 146.95

b. 157.85

c. 174.21

d. 333.05

e. 305.79

Answer: E

224. If X ~ N(μ, 25) and p(X > 12) = 0.3446. What is the value of μ?

a. 10.00

b. 5.90

c. 1.80

d. 8.05

e. 4.65

Answer: A

225. If X ~ N(μ, 25) and p(X > 12) = 0.1112. What is the value of μ?

a. 10.00

b. 5.90

c. 1.80

d. 8.05

e. 4.65

Answer: B

226. If X ~ N(μ, 25) and p(X > 12) = 0.0207. What is the value of μ?

a. 10.00

b. 5.90

c. 1.80

d. 8.05

e. 4.65

Answer: C

227. If X ~ N(μ, 25) and p(X > 12) = 0.2148. What is the value of μ?

a. 10.00

b. 5.90

c. 1.80

d. 8.05

e. 4.65

Answer: D

228. If X ~ N(μ, 25) and p(X > 12) = 0.0708. What is the value of μ?

a. 10.00

b. 5.90

c. 1.80

d. 8.05

e. 4.65

Answer: E