A reduction of 50% in the price of oil enables a house wife to obtain 5kgs more for Rs.800, what is the reduced price for kg?
Answers:
A) s . 42
B) s . 46
C) s . 40
D) s . 80
E) s . 34

Rationale: "800 * ( 50 / 100 ) = 400 - - - - 5 ? - - - - 1 = > rs . 80 answer : d"
Answer: D