Suppose that x is normally distributed with a mean of 30 and a standard deviation of 3. What is P(27.42 x 34.08)?

Suppose that x is normally distributed with a mean of 30 and a standard deviation of 3. What is P(27.42 ≤ x ≤ 34.08)?

a) 0.718

b) 0.413

c) 0.309

d) 0.305

e) 0.415

f) None of the above

Question 2

Find a value of c so that P(Z ≥ c) = 0.48.

a) 0.95

b) -0.05

c) 0.15

d) 0.05

e) 0.10

f) None of the above

Question 3

Suppose that x is normally distributed with a mean of 50 and a standard deviation of 9. What is P(33.53 ≤ x ≤ 70.97)?

a) 0.495

b) 0.466

c) 0.490

d) 0.956

e) 0.471

f) None of the above

Question 4

The length of time needed to complete a certain test is normally distributed with mean 24 minutes and standard deviation 11 minutes. Find the probability that it will take between 22 and 28 minutes to complete the test.

a) 0.5000

b) 0.4279

c) 0.1070

d) 0.7859

e) 0.2141

f) None of the above

Question 5

The length of time needed to complete a certain test is normally distributed with mean 23 minutes and standard deviation 11 minutes. Find the probability that it will take more than 20 minutes to complete the test.

a) 0.6075

b) 0.5000

c) 0.6963

d) 0.3925

e) 0.3037

f) None of the above