Question

Brett is performing a hypothesis test in which the population mean is 310 and the standard deviation is 20. his sample data has a mean of 295 and a sample size of 50. which of the following correctly depicts the z-statistic for brett’s data? –5.30 –0.11 4.28 6.27

Answer 1

According to the given data and applying it's formula, the z-statistic is of z = -5.30.

What is the z-statistic formula?

It is given by:

$z = \frac{\overline{x} - \mu}{\frac{\sigma}{\sqrt{n}}}$

The parameters are:

• $\overline{x}$ is the sample mean.

• $\mu$ is the value tested at the null hypothesis.

• $\sigma$ is the standard deviation of the population.

• n is the sample size.

In this problem, the values of the parameters are given by:

$\overline{x} = 295, \mu = 310, \sigma = 20, n = 50$

Hence, the z-statistic is given by:

$z = \frac{\overline{x} - \mu}{\frac{\sigma}{\sqrt{n}}}$

$z = \frac{295 - 310}{\frac{20}{\sqrt{50}}}$

z = -5.30.

The z-statistic is of z = -5.30.

More can be learned about z-statistic at  brainly.com/question/26454209

Answer 2

The z-statistic for Brett's data is found to be as given by: Option A: -5.30 (approx).

How to find the value of z-statistic for population mean?

Suppose we're specified that:

• The sample mean = $\overline{x}$
• The population mean = $\mu$
• The population standard deviation = $\sigma$
• The sample size = n

Then the z-statistic for this data is found as:

$Z = \dfrac{\overline{x} - \mu}{\sigma/\sqrt{n}}$

For this case, we've got:

• The sample mean = $\overline{x}$ = 295
• The population mean = $\mu$ = 310
• The population standard deviation = $\sigma$ = 20
• The sample size = n = 50

Thus, we get:

$Z = \dfrac{\overline{x} - \mu}{\sigma/\sqrt{n}} = \dfrac{295 - 310}{20/\sqrt{50}} \approx -5.30$

Thus, the z-statistic for Brett's data is found to be as given by: Option A: -5.30 (approx).

Learn more about z-statistic here:

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