Answer:
a. We fail reject to the null hypothesis because zo = -5.84 < 1.65 = zα and P-value = 1 (approximately)
b. The confidence Interval for u1 - u2 is; 6.79 ≤ u1 - u2
c. The power of the test = 1 -
β = 0.998736
d. The sample size is adequate because the power of the test is approximately 1
Step-by-step explanation:
Given
Standard Deviations; σ1 = σ2 = 1.0 psi
Size: n1 = 10; n2 = 12
X = 162.5; Y = 155.0
Let X1, X2....Xn be a random sample from Population 1
Let Y1, Y2....Yn be a random sample from Population 2
We assume that both population are normal and the two are independent.
Therefore, the test statistic
Z = (X - Y - (u1 - u2))/√(σ1²/n1 + σ2²/n2)
See attachment for explanation
