A reduction of 42% in the price of bananas would enable a man to obtain 64 more for Rs.40, what is reduced price per dozen? Pick one.
A) 2.15
B) 8.15
C) 7.15
D) 3.15
E) 1.15

Rationale: "explanation : 40 * ( 42 / 100 ) = 16.8 - - - 64 ? - - - 12 = > rs . 3.15 answer : d"
Answer: D