Question

You wish to test the following claim (Ha) at a significance level of α=0.05.

      Ho:μ1=μ2
      Ha:μ1>μ2

You obtain a sample of size n1=19 with a mean of ¯x1=51.9 and a standard deviation of s1=8.7 from the first population. You obtain a sample of size n2=9 with a mean of ¯x2=41.8 and a standard deviation of s2=6.6 from the second population.

Find a confidence interval for the difference of the population means. For this calculation, use the conservative under-estimate for the degrees of freedom as mentioned in the textbook. (Report answer accurate to three decimal places.)
confidence interval =

The test statistic is...

• the confidence interval contains zero
• all values in the confidence interval are below zero
• all values in the confidence interval are above zero

This test statistic leads to a decision to...

• reject the null
• accept the null
• fail to reject the null

As such, the final conclusion is that...

• There is sufficient evidence to warrant rejection of the claim that the first population mean is greater than the second population mean.
• There is not sufficient evidence to warrant rejection of the claim that the first population mean is greater than the second population mean.
• The sample data support the claim that the first population mean is greater than the second population mean.
• There is not sufficient sample evidence to support the claim that the first population mean is greater than the second population mean.

Answer 1