A is the average (arithmetic mean) of the first 7 positive multiples of 4 and B is the median of the first 3 positive multiples of positive integer n. If the value of A^2 – B^2 is zero, what is the value of n? Answers:  A) 2  B) 4  C) 6  D) 8  E) 10
If A^2 - B^2 = 0, then let's assume that A = B.   A must equal the 4th positive multiple of 4, thus A = 16, which also equals B.   B is the second positive multiple of n, thus n = 16/2= 
<gadget id="calculator">16/2</gadget>
<output>8</output>
8.   The answer is 8.
<result>D</result>
A is the average (arithmetic mean) of the first 7 positive multiples of 4 and B is the median of the first 3 positive multiples of positive integer n. If the value of A^2 – B^2 is zero, what is the value of n?