Question

Sales at a fast-food restaurant average $6,000 per day. The restaurant decided to introduce an advertising campaign to increase daily sales. In order to determine the effectiveness of the advertising campaign, a sample of 49 day's sales were taken. The sample showed average daily sales of $6,400. From past history, the restaurant knew that its population standard deviation is about $1,000. The value of the test statistic is ______.

Answer 1

The value of the test statistic is 2.8.

Explanation:

The test statistic is:

`z = (X - \mu)/((\sigma)/(√(n)))`

In which X is the sample mean,
`\mu` is the value expected value for the population mean,
`\sigma` is the standard deviation and n is the size of the sample.

Sales at a fast-food restaurant average $6,000 per day

This means that
`\mu = 6000`

Sample of 49

This means that
`n = 49`

The sample showed average daily sales of $6,400.

This means that
`X = 6400`

Population standard deviation is about $1,000.

This means that
`\sigma = 1000`

The value of the test statistic is

`z = (X - \mu)/((\sigma)/(√(n)))`

`z = (6400 - 6000)/((1000)/(√(49)))`

`z = 2.8`

The value of the test statistic is 2.8.