Data collected over a long period of time show that the length of time x to complete a particular college entrance test is normally distributed with an average of 125 minutes and a standard deviation of 18 minutes. What is the probability that a student taking this test will finish in 100 minutes or less? Round your answer to 4 decimal places. Remember to round all z values to 2 decimal places.
Choose one answer.
A. 0.9177
B. 0.7538
C. 0.0823
D. 0.1566
E. None of the above
Question 2
Marks: 8
Data collected over a long period of time show that the length of time x to complete a particular college entrance test is normally distributed with an average of 125 minutes and a standard deviation of 18 minutes. Ordinarily entrance tests have a time limit. What maximum time limit should be set for this entrance test if it is desired to have no more than 8% of test takers fail to finish the test during that time limit? Round your answer to the nearest minute. Don't forget that we round all z values to two decimal places.
To answer the question input only the actual whole number. Do not include units. Do not give your answer in sentence form -- just include the numerical answer.
Answer:
Question 3
Marks: 8
For a specific truck traveling at 50 miles per hour (mph), the distance x required to brake to a complete stop is normally distributed with a mean of 120 feet and a standard deviation of 12 feet. Suppose that this truck is traveling at a constant speed of 50 mph and a car abruptly moves into the path of the truck and stops at a distance of 150 feet from the truck. Assuming that the only way to avoid a collision is for the truck to brake to a complete stop, what is the probability that there will be a collision? Round your answer to 4 decimal places. Remember to round all z values to two decimal places.
Choose one answer.
A. 0.0062
B. 0.0186
C. 0.0239
D. 0.0268
E. None of the above
Question 4
Marks: 6
If z is a standard normal random variable and A is a positive number, then
P(z<-A)=P(z>A).
Answer: True
False