The One Sample Z Test

A lecture course has 900 students broken into sections of 30 students each. On the final the average of the whole class is 63 with an SD of 20. However one section has an average of only 54. The TA for the section argues his section's low average is just due to chance variation. The null hypothesis is that this TA is no different than the average TA and that the difference between his section's average and the whole class's average is small and just due to chance.

How many tickets are in the null box?

Tries 0/5

The null hypothesis is that the assignment of students to TAs' sections is like makingdraws.

Tries 0/5

The draws are made _________ replacement.

with

without

Tries 0/1

What is the expected value of the average of the draws?

Tries 0/5

What is the standard error of the average of the draws (round to two decimal places)?

Tries 0/5

What is the value of the test statistic z (use previously rounded answers in your calculations)?

Tries 0/3

What is the value of the p-value?

Tries 0/3

Does the TA have a good defense, is it plausible that the difference is just due to chance?

Yes, because the p-value is too small

No, we reject the null because the p-value is less than 5%

Yes, because the null hypothesis is accepted

Yes, because the p-value is bigger than 5%

No, we reject the null because the p-value is greater than 5%