Question

In: Statistics and Probability

A safety officer wants to prove that the average speed of cars driven by a school...

A safety officer wants to prove that the average speed of cars driven by a school is less than 25 mph. Suppose that a random sample of 14 cars shows an average speed of 24 mph, with a sample standard deviation of 2.2 mph. Assume that the speed of cars are normally distributed.
Provide the notation for the underlined value. That is, what does it represent?

Solutions

Expert Solution

Solution :

= 25

=24

S =2.2

n = 14

This is the left tailed test .

The null and alternative hypothesis is ,

H0 :    = 25

Ha : < 25

Test statistic = t

= ( - ) / S / n

= (24-25) / 2.2 / 14

= -1.701

Test statistic = t= -1.701  

P-value =0.0564


Related Solutions

A safety officer wants to prove that the average speed of cars driven by a school...
A safety officer wants to prove that the average speed of cars driven by a school is less than 25 mph. Suppose that a random sample of 14 cars shows an average speed of 24.0 mph, with a sample standard deviation of 2.2 mph. Assume that the speeds of cars are normally distributed. Provide the notation for the underlined value. That is, what does the underlined value represent?
Suppose the National Transportation Safety Board wants to examine the safety of compact cars, midsize cars,...
Suppose the National Transportation Safety Board wants to examine the safety of compact cars, midsize cars, and full-size cars. It collects a sample of three for each of the treatments (cars types). Test the claim that the mean pressure applied to the driver's head during a crash is equal for all three types of cars. Use α = 0.05 Compact Cars 643 655 702 Midsize Cars 469 427 525 Full-size Cars 484 456 402 Show your 6 steps labeled in...
Suppose the National Transportation Safety Board (NTSB) wants to examine the safety of compact cars, midsize...
Suppose the National Transportation Safety Board (NTSB) wants to examine the safety of compact cars, midsize cars, and full-size cars. It collects a sample of ten for each of the treatments (cars types). Using the hypothetical data provided below, test whether the mean pressure applied to the driver’s head during a crash test is equal for each types of car. At the 0.05 significance level, can we conclude that there is a difference in the mean pressures between compact, midsize...
Suppose the National Transportation Safety Board (NTSB) wants to examine the safety of compact cars, midsize...
Suppose the National Transportation Safety Board (NTSB) wants to examine the safety of compact cars, midsize cars, and full-size cars. It collects a sample of cars each of the cars types. The data below displays the frontal crash test performance percentages. Test whether there are statistical differences in the frontal crash test performance for each type of car. Compact Cars Midsize Cars Full-Size Cars 95 95 93 98 98 97 87 98 92 99 89 92 99 94 84 94...
7. Suppose the National Transportation Safety Board (NTSB) wants to examine the safety of compact cars,...
7. Suppose the National Transportation Safety Board (NTSB) wants to examine the safety of compact cars, midsize cars, and full-size cars. It collects a sample of three for each of the treatments (cars types). The hypothetical data provided below from 10 trials report the mean pressure applied to the driver’s head during a crash test for each type of car. Compact: 635, 671, 648, 685, 648, 651, 654, 682, 687, 627 Midsize: 482, 529, 541, 518, 497, 526, 507, 492,...
Suppose the National Transportation Safety Board (NTSB) wants to examine the safety of compact cars, midsize...
Suppose the National Transportation Safety Board (NTSB) wants to examine the safety of compact cars, midsize cars, and full-size cars. It collects a sample of three for each of the treatments (cars types). Using the data provided below, test whether the mean pressure applied to the driver’s head during a crash test is equal for each types of car. Use α = 5%. Compact cars Midsize cars Full-size cars 64 46 47 65 43 45 69 52 40 Average: 66...
Suppose the National Transportation Safety Board (NTSB) wants to examine the safety of compact cars, midsize...
Suppose the National Transportation Safety Board (NTSB) wants to examine the safety of compact cars, midsize cars, and full-size cars. It collects a sample of three for each of the car types. Using the data provided below Pressure Car Type 643 Compact 655 Compact 702 Compact 469 MidSize 427 MidSize 525 MidSize 484 FullSize 456 FullSize 402 FullSize Test, using Mood’s Median Test, whether the median pressure applied to the driver’s head during a crash test is equal for each...
Suppose the National Transportation Safety Board (NTSB) wants to examine the safety of compact cars, midsize...
Suppose the National Transportation Safety Board (NTSB) wants to examine the safety of compact cars, midsize cars, and full-size cars. It collects a sample of cars each of the cars types. The data below displays the frontal crash test performance percentages. Compact Cars Midsize Cars Full-Size Cars 95 95 93 98 98 97 87 98 92 99 89 92 99 94 84 94 88 87 99 93 88 98 99 89 Patrick wants to purchase a new car, but he...
Greg wants to compare the top speed of the fastest cars in the world to determine...
Greg wants to compare the top speed of the fastest cars in the world to determine which car is faster, the Hennessy Venom GT or the Bugatti Veyron. He gets the guys from Top Gear to take the cars on the track to determine if one car is faster than the other. Since the cars are privately owned, they only allow for 5 test runs. Is the venom significantly faster than the Bugatti? Trial   1   2   3   4   5               Bugatti...
Suppose you want to estimate the average mpg for cars being driven from campus to the...
Suppose you want to estimate the average mpg for cars being driven from campus to the Brass Rail. You sample a few of cars. The average mpg in your sample is 22, and the standard deviation is 10. If you want the error of the confidence interval to be no greater than 0.3 and to be 90% likely to contain the true population mean, how many cars should you randomly sample? Group of answer choices A)about 3,007 cars B)about 9,112...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT