A psychology researcher has a theory that predicts women will tend to carry more cash than men. A random sample of Ersatz University students revealed that 16 females had a mean of $22.30 in their wallets with a standard deviation of $3.20, while 16 males had a mean of $17.30 with a standard deviation of $9.60. The test statistic for the researcher’s hypothesis is:

Respuesta :

Answer: t=5.59

Step-by-step explanation:

We assume that the money in wallets of women and men are normally distributed.

Given : Sample size of females : [tex]n_x=16[/tex]

Sample mean : [tex]\overline{X}=22.30[/tex]

Standard deviation : [tex]\sigma_x=3.20[/tex]

Sample size of males : [tex]n_y=16[/tex]

Sample mean : [tex]\overline{Y}=22.30[/tex]

Standard deviation : [tex]\sigma_y=9.60[/tex]

Since sample size is small (<30), so we use t-test.

The test static for difference of two population mean is given by :-

[tex]t=\dfrac{\overline{X}-\overline{Y}}{\sqrt{\dfrac{\sigma_x}{n_x}+\dfrac{\sigma_y}{x_y}}}[/tex]

[tex]=\dfrac{22.30-17.30}{\sqrt{\dfrac{3.20}{16}+\dfrac{9.60}{16}}}\\\\=5.59016994375\approx5.59[/tex]

Hence, the test statistic for the researcher’s hypothesis is : t=5.59