The banker's gain of a certain sum due 3 years hence at 10% per annum is Rs. 36. What is the present worth ? Pick one:
A) rs . 400  B) rs . 300  C) rs . 500  D) rs . 350  E) none of these

Rationale: "explanation : t = 3 years r = 10 % td = ( bg × 100 ) / tr = ( 36 × 100 ) / ( 3 × 10 ) = 12 × 10 = rs . 120 td = ( pw × tr ) / 100 ⇒ 120 = ( pw × 3 × 10 ) / 100 ⇒ 1200 = pw × 3 pw = 1200 / 3 = rs . 400 answer : option a"
Answer: A