The slant shear test is widely accepted for evaluating the bond

The slant shear test is widely accepted for evaluating the bond of resinous repair materials to concrete; utilizes cylinder specimens made of two identical halves bonded at 30°. An article reported specimens prepared using wire-brushing, the sample mean shear strength (N/mm2) and sample standard deviation were 18.800 and 1.55, respectively, whereas for 11 hand-chiseled that for specimens, the corresponding values were 23.11 and 4.03. Does the true average strength appear to be different for the two methods of surface preparation? State and test the relevant hypotheses using a significance level of 0.05. (Use for wire-brushing and , for hand-chiseling.

 о 3 F - я:°н с о - 1 - :°н с 0 - :H о> - й :PA Ho HH2= 0 Ha 20

 Calculate the test statistic and determine the P-value. (Round your test statistic to two decimal places and your P-value to three decimal places.

 t= P-value

State the conclusion in the problem context.

 Fail to reject H. The data suggests that the true average strength is not different for the two methods of surface preparation

Reject H The data suggests that the true average strength is not different for the two methods surface preparation.

Reject Ho The data suggests that the true average strength is different for the two methods of surface preparation

Fail to reject Hn. The data suggests that the true average strength is not different for the two methods of surface preparation.

 What are you assuming about the shear strenqth distributions?

It is assumed that distributions for both preparation types are normal.

It is assumed that distributions for both preparation types are the same.

It assumed that variances of distributions for both preparation types are equal.

It assumed that means of distributions for both preparation types are equal