# Question: In a mechanical testing lab Plexiglass strips are stretched to

In a mechanical testing lab, Plexiglass strips are stretched to failure. Let X equal the change in length in mm before breaking. Assume that the distribution of X is N(μ, σ2). We shall test the null hypothesis H0: μ = 5.70 against the alternative hypothesis H1: μ > 5.70, using n = 8 observations of X.

(a) Define the test statistic and a critical region that has a significance level of α = 0.05. Sketch a figure showing this critical region.

(b) A random sample of eight observations of X yielded the following data:

Calculate the value of the test statistic and state your conclusion clearly.

(c) Give the approximate value of or bounds for the p-value of this test.

(a) Define the test statistic and a critical region that has a significance level of α = 0.05. Sketch a figure showing this critical region.

(b) A random sample of eight observations of X yielded the following data:

Calculate the value of the test statistic and state your conclusion clearly.

(c) Give the approximate value of or bounds for the p-value of this test.

**View Solution:**## Answer to relevant Questions

To test whether a golf ball of brand A can be hit a greater distance off the tee than a golf ball of brand B, each of 17 golfers hit a ball of each brand, 8 hitting ball A before ball B and 9 hitting ball B before ball A. ...A company that manufactures brackets for an automaker regularly selects brackets from the production line and performs a torque test. The goal is for mean torque to equal 125. Let X equal the torque and assume that X is ...Let X and Y equal the forces required to pull stud No. 3 and stud No. 4 out of a window that has been manufactured for an automobile. Assume that the distributions of X and Y are N(μX, σ2x) and N(μY, σ2Y), ...It was claimed that 75% of all dentists recommend a certain brand of gum for their gum-chewing patients. A consumer group doubted this claim and decided to test H0: p = 0.75 against the alternative hypothesis H1: p < 0.75, ...Let m equal the median of the posttest grip strengths in the right arms of male freshmen in a study of health dynamics. We shall use observations on n = 15 such students to test the null hypothesis H0: m = 50 against the ...Post your question