The simple interest and the true discount on a certain sum for a given time and at a given rate are Rs. 85 and Rs. 80 respectively.The Sum is : Choose the most appropriate option
A) Rs. 1800 B) Rs. 1450 C) Rs. 1360 D) Rs. 6800 E) None
Solution   Sum = S.I xT.D/ ( S.I) - ( T.D)= 85 x80/85 - 80=Rs.1360.   Answer Rs. 1360
<result>C</result>
The simple interest and the true discount on a certain sum for a given time and at a given rate are Rs. 85 and Rs. 80 respectively.The Sum is :