this week's MGRE Math Beast Challenge problem

From here:

f(x) = 0.27(-3.12x – 4)

Set P consists of n distinct values, where n > 1. Set Q consists of the n values that result from inputting the n distinct values from Set P into f(x).

Quantity A
The standard deviation of Set P

Quantity B
The standard deviation of Set Q

(A) Quantity A is greater

(B) Quantity B is greater

(C) The two quantities are equal.

(D) The relationship cannot be determined from the information given.

Go to it! My own answer will eventually appear in the comments... but first, I really need to review standard deviations!

(Some help can be found here.)


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