# Question: A manufacturing company produces electrical insulators If the insulators break

A manufacturing company produces electrical insulators. If the insulators break when in use, a short circuit is likely to occur. To test the strength of the insulators, destructive testing is carried out to determine how much force is required to break the insulators. Force is measured by observing the number of pounds of force applied to the insulator before it breaks. The following data (stored in Force) are from 30 insulators subjected to this testing:

a. At the 0.05 level of significance, is there evidence that the population mean force required to break the insulator is greater than 1,500 pounds?

b. What assumption about the population distribution is needed in order to conduct the t test in (a)?

c. Construct a histogram, boxplot, or normal probability plot to evaluate the assumption made in (b).

d. Do you think that the assumption needed in order to conduct the t test in (a) is valid? Explain.

a. At the 0.05 level of significance, is there evidence that the population mean force required to break the insulator is greater than 1,500 pounds?

b. What assumption about the population distribution is needed in order to conduct the t test in (a)?

c. Construct a histogram, boxplot, or normal probability plot to evaluate the assumption made in (b).

d. Do you think that the assumption needed in order to conduct the t test in (a) is valid? Explain.

## Answer to relevant Questions

An important quality characteristic used by the manufacturer of Boston and Vermont asphalt shingles is the amount of moisture the shingles contain when they are packaged. Customers may feel that they have purchased a product ...A bank with a branch located in a commercial district of a city has the business objective of developing an improved process for serving customers during the noon- to- 1 p. m. lunch period. Management decides to first study ...Nine experts rated two brands of Colombian coffee in a taste testing experiment. A rating on a 7 point scale (1 = extremely unpleasing, 7 = extremely pleasing) is given for each of four characteristics: taste, aroma, ...Let n1 = 100, X1 = 45, n2 = 50, and X2 = 25. a. At the 0.01 level of significance, is there evidence of a significant difference between the two population proportions? b. Construct a 99% confidence interval estimate for ...Determine the upper tail critical value of F in each of the following one tail tests. a. α = 0.05, n1 = 16, n2 = 21 b. α = 0.01, n1 = 16, n2 = 21Post your question