1. An engineer designed a valve that will regulate waterpressure on an automobile engine. The engineer designed the valvesuch that it would produce a mean pressure of 4.2 pounds/squareinch. It is believed that the valve performs above thespecifications. The valve was tested on 150 engines and the meanpressure was 4.3 pounds/square inch. Assume the standard deviationis known to be 0.8. A level of significance of 0.05 will be used.Determine the decision rule.
Enter the decision rule.
2. A lumber company is making doors that are 2058.0 millimeterstall. If the doors are too long they must be trimmed, and if thedoors are too short they cannot be used. A sample of 20 is made,and it is found that they have a mean of 2047.0 millimeters with astandard deviation of 30.0. A level of significance of 0.1 will beused to determine if the doors are either too long or too short.Assume the population distribution is approximately normal. Findthe value of the test statistic. Round your answer to three decimalplaces.
3. An engineer designed a valve that will regulate waterpressure on an automobile engine. The engineer designed the valvesuch that it would produce a mean pressure of 7.9 pounds/squareinch. It is believed that the valve performs above thespecifications. The valve was tested on 24 engines and the meanpressure was 8.1 pounds/square inch with a variance of 0.25. Alevel of significance of 0.1 will be used. Assume the populationdistribution is approximately normal. Make the decision to rejector fail to reject the null hypothesis.
4. A manufacturer of banana chips would like to know whether itsbag filling machine works correctly at the 413.0 gram setting. Itis believed that the machine is underfilling the bags. A 33 bagsample had a mean of 406.0 grams. A level of significance of 0.02will be used. Is there sufficient evidence to support the claimthat the bags are underfilled? Assume the variance is known to be256.00.
What is the conclusion?
A. There is not sufficient evidence to support the claim thatthe bags are undefilled.
B. There is sufficient evidence to support the claim that thebags are underfilled.
5.
A manufacturer of chocolate chips would like to know whether itsbag filling machine works correctly at the 404.0 gram setting. Itis believed that the machine is underfilling the bags. A 39 bagsample had a mean of 400.0 grams. A level of significance of 0.05will be used. Is there sufficient evidence to support the claimthat the bags are underfilled? Assume the standard deviation isknown to be 26.0.
What is the conclusion?
A. There is not sufficient evidence to support the claim thatthe bags are undefilled.
B. There is sufficient evidence to support the claim that thebags are underfilled.
