if price of t.v set is reduced by 25%, then its sale increases by 75%, find net effect on sale value  Choose one.
A) 31	B) 32	C) 46	D) 47	E) 48

Rationale: "- a + b + ( ( - a ) ( b ) / 100 ) = - 25 + 75 + ( - 25 * 75 ) / 100 = - 25 + 75 - 19 = 31 answer : a"
Answer: A