If 10% of 30% of 50% of a number is 90, then what is the number? Choose the correct choice:	A) 4000	B) 6000	C) 4400	D) 4500	E) none of these

Rationale: "let the number be a given , 10 / 100 * 30 / 100 * 50 / 100 * a = 90 = > 1 / 10 * 3 / 10 * 1 / 2 * a = 90 = > a = 10 * 20 * 10 * 2 = 6000 . answer : b"
Answer: B