The present worth of a certain sum due sometime hence is Rs. 3400 and the true discount is Rs. 340. The bankers gain is:
Rs. 21
Rs. 17
Rs. 18
Rs. 34
Explanation:
$BG =\dfrac{{TD}^2 }{PW} = \dfrac{{340}^2 }{3400}$
$= \dfrac{340 \times 340 }{3400} = \dfrac{340}{10} = Rs.34$