If a*b*c=130, b*c*d = 65, c*d*e=1000 and d*e*f=250 the (a*f)/(c*d) = ?
Answers:
A) 1 / 2	B) 1 / 4	C) 3 / 4	D) 2 / 3	E) none of these

Rationale: "explanation : a ∗ b ∗ c / b ∗ c ∗ d = 130 / 65 = > a / d = 2 d ∗ e ∗ f / c ∗ d ∗ e = 250 / 1000 = > f / c = 14 a / d * f / c = 2 * 1 / 4 = 1 / 2 answer : a"
Answer: A