Answer:
The training does reduce response time at 0.05 level of significance
Step-by-step explanation:
Population mean for a population with normal distribution, where the standard deviation is known and the appropriate significant test is given then;
z=x-μ / δ/√n
where
μ= 9 minutes
x=8 minutes
δ= 4.2
n= 36
Applying the formula;
z= 8-9 / 4.2/√36
z= -1 / 4.2/6
z= -1 /0.7 = - 1.429
Perform the test where
H₀ : p=0.05 verse Ha : p < 0.05
Using the Z-table, find the probability that Z is less than -1.43.
You will find the probability of 0.0764 of Z being more than the value in test thus; there are high chances that results will be observed according to the null hypothesis