If a*b*c=195, b*c*d = 65, c*d*e=1000 and d*e*f=250 the (a*f)/(c*d) = ?	Select:
A) 1 / 2  B) 1 / 4  C) 3 / 4  D) 2 / 3  E) none of these

Rationale: explanation : a â ˆ — b â ˆ — c / b â ˆ — c â ˆ — d = 195 / 65 = > a / d = 3 d â ˆ — e â ˆ — f / c â ˆ — d â ˆ — e = 250 / 1000 = > f / c = 1 / 4 a / d * f / c = 3 * 1 / 4 = 3 / 4 answer : c
Answer: C