A mixture of pulverized fuel ash and Portland cement to be used for grouting should have a compressive strength of more than 1300 KN/m^2. 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 σ = 63. Let μ denote the true average compressive strength.
a. What are the appropriate null and alternative hypothesis?

We are given that a mixture of pulverized fuel ash and Portland cement to be used for grouting should have a compressive strength of more than 1300 KN/m^2.

Suppose compressive strength for specimens of this mixture is normally distributed with σ = 63.

Let [tex]\mu[/tex] = the true average compressive strength

So, Null Hypothesis, [tex]H_0[/tex] : [tex]\mu\leq[/tex] 1300 KN/m^2

Alternate Hypothesis, [tex]H_A[/tex] : [tex]\mu[/tex] > 1300 KN/m^2

Here, null hypothesis states that the compressive strength of pulverized fuel ash and Portland cement is less than or equal to 1300 KN/m^2.

On the other hand, alternate hypothesis sates that the compressive strength of pulverized fuel ash and Portland cement is more than 1300 KN/m^2.

So, this would be the appropriate null and alternative hypothesis.