Free notebooks were distributed equally among children of a class. The number of notebooks each child got was one-eighth of the number of children. Had the number of children been half, each child would have got 16 notebooks. Total how many notebooks were distributed?	Select:
A) 256 B) 512 C) 432 D) 352 E) 640

Rationale: let total number of children be x . then , x * ( 1 / 8 ) x = ( x / 2 ) x 16 x = 64 . number of notebooks = ( 1 / 8 ) x ^ 2 = ( 1 / 8 ) x 64 x 64 = 512 . answer is b .
Answer: B