Strength of concrete: The compressive strength, in kilopascals, was measure for concrete blocks from five different...

Strength of concrete: The compressive strength, in kilopascals, was measure for concrete blocks from five different batches of concrete, both three and six days after pouring. The data are as follows:

	Block
	1	2	3	4	5
After 3 days	1341	1316	1352	1355	1327
After 6 days	1376	1373	1366	1384	1358

Can you conclude that the mean strength after three days differs from the mean strength after six days? Use the α = 0.05 level of significance.

State the null and alternative hypothesis

Compute the p-value and Testing Value

Do you reject the null hypothesis? Explain?

Can you conclude that the mean strength after three days differs from the mean strength after six days?

Solutions

Expert Solution

Let us denote the difference

d = After 3 days - After 6 days

There is sufficient evidence to support the claim that the mean strength after three days differs from the mean strength after six days

orchestra answered 1 year ago

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