. A cigarette company claims the average amount of tar per cigarette is 14 mg pe

ID: 3177785 • Letter: #

Question

. A cigarette company claims the average amount of tar per cigarette is 14 mg per cigarette. The amount of tar in the population is known to vary on average about 0.6 mg/cigarette. An independent research firm tests whether the average amount of tar is greater than the claimed 14mg/cigarette from a random sample of 100 cigarettes. The firm calculates the sample average to be 14.4mg per cigarette. What is the parameter of interest? Is the parameter categorical or quantitative? What type of procedure is appropriate for this scenario and why?

Explanation / Answer

Result:

A cigarette company claims the average amount of tar per cigarette is 14 mg per cigarette. The amount of tar in the population is known to vary on average about 0.6 mg/cigarette. An independent research firm tests whether the average amount of tar is greater than the claimed 14mg/cigarette from a random sample of 100 cigarettes. The firm calculates the sample average to be 14.4mg per cigarette.

What is the parameter of interest?

Parameter: population mean amount of tar per cigarette

Is the parameter categorical or quantitative?

The parameter is quantitative.

What type of procedure is appropriate for this scenario and why?

Single sample z test is used to compare sample mean with population mean since population standard deviation is given.

Z Test of Hypothesis for the Mean

Data

Null Hypothesis m=

Level of Significance

0.05

Population Standard Deviation

0.6

Sample Size

100

Sample Mean

14.4

Intermediate Calculations

Standard Error of the Mean

0.0600

Z Test Statistic

6.6667

Upper-Tail Test

Upper Critical Value

1.6449

p-Value

0.0000

Reject the null hypothesis