Respuesta :
Answer:
The p-value of the test is 0.001 < 0.05, which means that there is evidence at the 0.05 level of significance that the mean one-time gift donation is greater than $70.
Step-by-step explanation:
Test if the mean one-time gift donation is greater than $70:
At the null hypothesis, we test if it is 70 or less, that is:
[tex]H_0: \mu \leq 70[/tex]
At the alternate hypothesis, we test if it is greater than 70, that is:
[tex]H_1: \mu > 70[/tex]
The test statistic is:
[tex]t = \frac{X - \mu}{\frac{s}{\sqrt{n}}}[/tex]
In which X is the sample mean, [tex]\mu[/tex] is the value tested at the null hypothesis, s is the standard deviation of the sample and n is the size of the sample.
70 is tested at the null hypothesis:
This means that [tex]\mu = 70[/tex]
Based on a random sample of 60 nonprofit organizations, the mean one-time gift donation in the past year was $75, with a standard deviation of $12.
This means that [tex]n = 60, X = 75, s = 12[/tex].
Test statistic:
[tex]t = \frac{X - \mu}{\frac{s}{\sqrt{n}}}[/tex]
[tex]t = \frac{75 - 70}{\frac{12}{\sqrt{60}}}[/tex]
[tex]t = 3.23[/tex]
P-value of the test:
The p-value of the test is the probability of finding a sample mean above 75, which is a right-tailed test with t = 3.23 and 60 - 1 = 59 degrees of freedom.
Using a t-distribution calculator, this p-value is of 0.001.
The p-value of the test is 0.001 < 0.05, which means that there is evidence at the 0.05 level of significance that the mean one-time gift donation is greater than $70.
