If two samples are used in a hypothesis test for which the combined degrees of freedom is 27, which one of the following might be true about the two sample sizes?
A) Sample A = 14; Sample B = 13
B) Sample A = 12; Sample B = 13
C) Sample A = 15; Sample B = 14
D) Sample A = 20; Sample B = 8

Question

Quizplus · Accepted Answer

To find the combined degrees of freedom, we add the degrees of freedom for each sample. The degrees of freedom for a sample are the sample size minus one. So, we need to find two numbers that add up to 27 and where one number is 1 less than the other. The only choice that fits this is C: Sample A = 15; Sample B = 14. Sample A has 14 degrees of freedom (15-1 = 14) and Sample B has 13 degrees of freedom (14-1 = 13). The other choices either do not add up to 27 or do not have one sample size that is 1 less than the other.

If Two Samples Are Used in a Hypothesis Test for Which