What is the rate percent when the simple interest on Rs.600 amount to Rs.160 in 4 Years?  Pick one.
A) 6.66 %  B) 7.66 %  C) 6.06 %  D) 6.16 %  E) 8.66 %

Rationale: "160 = ( 600 * 4 * r ) / 100 r = 6.66 % answer : a"
Answer: A