Q:

The University of Florida is interested in determining if there is a difference in the amount of money spent on food every two weeks between male and female students. They take a random sample of 20 male students (group 2) and 20 female students (group 1). They also find that xbar2 is 132 with a standard deviation of 13, and xbar1 is 131 with a standard deviation of 38. Do not assume equal variances. Find the test statistic for the difference in the amount of money spent. (Round your answer to one number after the decimal.)

Accepted Solution

A:
Answer: -0.1Step-by-step explanation:Given : [tex]n_1=n_2=20[/tex][tex]\overline{x}_1=131\ ;\ \overline{x}_2=132[/tex][tex]s_1=38\ ;\ s_2=13[/tex]Test statistic for the difference in population mean is given by :-[tex]z=\dfrac{\overline{x}_1-\overline{x}_2}{\sqrt{\dfrac{s_1^2}{n_1}+\dfrac{s_2^2}{n_2}}}[/tex]i.e. [tex]z=\dfrac{131-132}{\sqrt{\dfrac{(38)^2}{20}+\dfrac{(13)^2}{20}}}[/tex]i.e. [tex]z=\dfrac{-1}{\sqrt{80.65}}[/tex]i.e. [tex]z=-0.111351946748\approx-0.1[/tex]Hence, the  test statistic for the difference in the amount of money spent: z=-0.1