Question

A student claims that the population mean of weight of TWST students is NOT 58kg. A random sample of 25 is tested and the sample mean is 62kg. Assume the weight is normally distributed with the population standard deviation 2.8kg. We will do a hypothesis testing at 5% level of significance to test the claim. (a) (10) Set up the null hypothesis and alternative hypothesis. (b) (5) Which test should we use? Upper-tailed test? Lower-tailed test? Two-tailed test? (c) (10) Find the Z-value of the test statistic. (d) (5) Find the p-value for the test statistic. (e) (10) Explain the meaning of p-value. (f) (10) Should we reject the null hypothesis? Use the result of (d) to explain the reason.

Answer 1

Here since the population standard deviation is given we will use Z test for mean.

follow the below steps to conduct the hypothesis.

a)

b) We will use Z test for one mean.

This is a two-tailed test

c)

d)

The p-value is p = 0,

e) Since p=0 < 0.05, it is concluded that the null hypothesis is rejected.

We have evidence to support the claim that the population mean of weight of TWST students is NOT 58kg