Consider the following hypothesis test

H_o : µ ≤ 15
H_a : µ >15

A sample of 100 provided a Sample mean of 14.5. The population Standard deviation is 5. The value of the test statistic is:

-1

The correct answer is Option (3) → -1

$Z = \frac{\bar{X} - \mu}{\sigma / \sqrt{n}}$

$Z = \frac{14.5 - 15}{5 / \sqrt{100}}$

$= \frac{-0.5}{5/10} = \frac{-0.5}{0.5} = -1$

$\text{Test statistic} = -1$