SOLVE BOLDED. GIVE EXACT ANSWER. A mixture of pulverized fuel ash and Portland c

Question

SOLVE BOLDED. GIVE EXACT ANSWER.

A mixture of pulverized fuel ash and Portland cement to be used for grouting should have a compressive strength of more than 1300 KN/m2. The mixture will not be used unless experimental evidence indicates conclusively that the strength specification has been met. Suppose compressive strength for specimens of this mixture is normally distributed with = 59. Let denote the true average compressive strength.

(a) What are the appropriate null and alternative hypotheses?

(b) Let

X

denote the sample average compressive strength for n = 11 randomly selected specimens. Consider the test procedure with test statistic

X

itself (not standardized). What is the probability distribution of the test statistic when H0 is true?

If

X = 1340,

find the P-value. (Round your answer to four decimal places.)
P-value =  

Should H0 be rejected using a significance level of 0.01?

(c) What is the probability distribution of the test statistic when = 1350?

State the mean and standard deviation of the test statistic. (Round your standard deviation to three decimal places.)

mean= _______________KN/m2

standard deviation=_____________ KN/m2

For a test with = 0.01, what is the probability that the mixture will be judged unsatisfactory when in fact = 1350 (a type II error)? (Round your answer to four decimal places.)

You may need to use the appropriate table in the Appendix of Tables to answer this question.

Explanation / Answer

a)

H0: = 1300
Ha: > 1300

1340 - 1300 / 59

Z = 0.68

P value : 0.2483

do not reject Ho

The test statistic has a normal distribution

Related Questions

Navigate

• Browse (All)
• Browse S
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.