Hypothesis test - mean (single small sample) Operating temp.

The mean operating temperature of an aircraft engine during level cruize is supposed to be 190 degrees. An airline tested one particular engine at randomly selected times. The mean temperature on these 25 tests was 193 degrees, with a standard deviation of 3 degrees. Should the pilot worry about th engine running hot? Conduct the appropriate hypothesis test at a significance level of 0.05.

Solution Preview

See the attached file for complete solution. The text here may not be copied exactly as some of the symbols / tables may not print.

Step 1: Set the hypothesis. The claim made will be the alternate hypothesis.
H0: = 190
H1: > 190

Step 2: Set the Level of ...

Solution Summary

This post explains the step-by-step process for conducting five-step hypothesis testing for mean with one sample. The steps are explained with formulas and calculations along with interpretation of the final results. The post will help students learn the hypothesis testing and result interpretation in easy way.

1.Why would you use a small sample to draw inference about a large population?
Test of a single proportion:
2. What is the difference between a sample parameter (X-bar and s) and a proportion parameter (p)?
Test of two populations, large sample size (z-statistics)
3. When would you use two population test with a larg

Question :
The mean score on a standardized psychology test is supposed to be 50. Believing that a group of psychologists will score higher, we test a random sample of 11 psychologists. Their mean score is 45 with s=3. Test at a level of significance of 1%.

A recent report from the American Medical Association claims that for the first time in ten years, the average salary of psychiatrists was greater than $190,000 with a standard deviation of $27,000. What is the null hypothesis for his claim?
The Eagle Ridge Contractors Association claims the average price of a home in their

Suppose that a small college claims that they graduate at least 500 students every semester. A random sample of 31 semesters yields a sample mean of 420 with a sample standard deviation of 65.
H0: m >= 500
Ha: m < 500
Find the critical value for the hypothesistest. Assume that the significance level is a=0.02.
Answe

1
Identifying the indicated value using Statdisk
Data Set 2 in Statdisk (Body temp) includes a sample of 106 body temperatures with a mean of 98.20 F. Assume that σ is known to be 0.62F. Consider a hypothesistest that uses a 0.05 significance level to test the claim that the mean body temperature of the population is l

Hypothesis, Null and Alternative, & P-values
Q1: What is a p-value in testing hypothesis?
Q2: How does this p-value help us to decide to/not to reject a Null hypothesis? What might happen if we do not use this p-value in particular, when we are rejecting a Null hypothesis?
Q3: What are the limits of these p-values t

A medical research study showed that the average weight of a newborn twin in 1988 was 5.1 lb. To determine if this year's average exceeds the 1988 mean of 5.1 lb., we would test the hypothesis;
Ho (null hypothesis): mu = 5.1 lb.
Ha (alternative hypothesis): mu > 5.1 lb.
Where mu is the actual mean

Please see the attached file.
A hypothesistest is used to test a claim. You get 1.75 as your test statistic and 1.59 as your critical value for a right-tailed test. Which of the following is the correct decision statement for the test?
A. Reject the null hypothesis
B. Claim the null hypothesis i