Question

Suppose we are testing the null hypothesis H 0 mu=20 and the alternative H iu =20 , normal population with sigma=6 A random sample of nine observations are drawn from the population, and we find the sample mean of these observations x = 17 The value of the test statistic z is approximatel

Answer 1

The value of the test statistic is
`z = -1.5`

Explanation:

The formula for the test statistic is:

`z = (X - \mu)/((\sigma)/(√(n)))`

In which X is the statistic,
`\mu` is the mean,
`\sigma` is the standard deviation and n is the number of observations.

In this problem, we have that:

`\mu = 20, X = 17, \sigma = 6, n = 9`

So

`z = (X - \mu)/((\sigma)/(√(n)))`

`z = (17 - 20)/((6)/(√(3)))`

`z = -1.5`

The value of the test statistic is
`z = -1.5`