Consider the following hypothesis test :
$H_0: \mu ≤ 30$
$H_a : \mu > 30 $
A sample of 49 provided a sample mean of 31.5. The population standard deviation is 3. The value of the test statistic is :
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → 3.5
The z-score formula is,
$z=\frac{\bar x-μ}{σ/\sqrt{n}}$
$=\frac{31.5-30.0}{3/\sqrt{49}}=\frac{1.5}{0.4286}$
$≃3.5$