The average of non-zero number and its square is 5 times the number. The number is?
Choose the correct choice from the following choices:
A) 9  B) 8  C) 6  D) 4  E) 3

Rationale: "let the number be x . then , ( x + x 2 ) / 2 = 5 x = > x 2 - 9 x = 0 = > x ( x - 9 ) = 0 = > x = 0 or x = 9 so , the number is 9 . answer : a"
Answer: A