Advanced topic: If a study has 18 participants in the experimental group and 7 in the control group,the harmonic mean will be closest to a value of
A)5
B)7
C)18
D)25

Question

Quizplus · Accepted Answer

The harmonic mean formula for two sample sizes is (2ab)/(a+b), where a and b are the sample sizes of the two groups. Plugging in the values from the question, we get (2 x 18 x 7)/(18+7) = 252/25. The closest value to this is 10, which is closest to choice B. Therefore, B is the best choice.

Advanced Topic: If a Study Has 18 Participants in the Experimental