[SPOILER, PPP+3] SD question

Hi all,

How would you all solve this one? D is not correct.

Hey! I think D is correct. Can you please check the answer key again?

D is correct.

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yea it’s D, could you please explain how you got that?

CASE I : Let’s assume that height of every person in quantity A is 65, then the mean will be 65 and the standard deviation which is the distance from the mean will be 0. Assume every person is 65 inches tall for quantity B too. In this case, the mean will be again 65 and SD will be 0 again. So we go with C.
CASE II : Let;s assume every person is 65 inches tall in quantity A, then again the SD will be 0. For quantity B, let us assume that the mean is 65 and all the people below mean are 64 inches tall and all the people above the mean are 66 inches tall. In this case, the SD will be …1,1,1,0,1,1,1… which will be greater than 0.
In CASE I, both the quantities are equal and in CASE II, they are not equal. So we go with D.

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