Answer
Step 1 : $H_0$: µ $\leq$ 8121 dollars , $H_1$: µ > 8121 dollars
Step 2: Since α = 1-0.01=0.99, and the test is a right-tailed test, the critical value is 2.33.
Step 3:
$\bar{X}$ = 8350 dollars, µ =8121 dollars, σ =750 dollars, n = 40
Test value = z = $\frac{\bar{X}- µ }{σ / \sqrt n}$
= $\frac{8350 - 8121 }{750 / \sqrt 40}$
= 1.93
Step 4 : Since the test value falls beyond the critical value, the decision is to reject the null hypothesis.
Step 5: There is enough evidence to support the claim that the average is greater than 8121 dollars
