Answer:
Calculated value Z = 2.1097 > 1.96 at 0.05 level of significance
There is a difference between the means
Explanation:
Step(i):-
Given that mean of the Population = 5.9pounds/square inch
Given mean of the sample = 6.0pounds/square inch
Given that variance of the Population = 0.36
The standard deviation of the Population = √0.36 =0.6
critical value (Z₀.₀₅)= 1.96
Step(ii):-
Null Hypothesis:H₀: x⁻ = μ
Alternative Hypothesis:H₁: x⁻ ≠ μ
Test statistic

Z = 2.1097
Final answer:-
Calculated value Z = 2.1097 > 1.96 at 0.05 level of significance
The null hypothesis is rejected
There is a difference between the means