The banker's discount on Rs. 1600 at 15% per annum is the same as true discount on Rs. 1680 for the same time and at the same rate. The time is: Select:  A) 3 months  B) 4 months  C) 5 months  D) 6 months  E) 7 months
S.I. on Rs. 1600 = T.D. on Rs. 1680.   Rs. 1600 is the P.W. of Rs. 1680, i.e., Rs. 80 is on Rs. 1600 at 15%.   Time = (100x80)/(1600x15)= 1/3 year = 4 months   answer : 4 months
<result>B</result>
The banker's discount on Rs. 1600 at 15% per annum is the same as true discount on Rs. 1680 for the same time and at the same rate. The time is: