Answer
The weight loss of 0.9 pounds is not significant as we fail to reject the Null Hypothesis. A larger sample makes it more likely that the null hypothesis will be rejected.
Work Step by Step
Here we have $H_{o}$: μ = 0, $H_{a}$: μ > 0, n = 40, x̅ = 0.9, s = 7.2 and α = 0.10
Using the classical approach:
Using Table VI, we have: t = 1.304
$σ_{ x̅} = \frac{s}{\sqrt n} = \frac{7.2}{\sqrt 40} = 1.138$
$t = \frac{0.9 - 0}{1.138} = 0.791$
Since, 0.791 < 1.304, we fail to reject the Null hypothesis.
