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:	Pick.
A) Rs. 1800 B) Rs. 1450 C) Rs. 1360 D) Rs. 6800 E) Rs. 7800
sum=si*td/(si-td)   sum=80*85/(85-80)= 
<gadget id="calculator">80*85/(85-80)</gadget>
<output>1_360</output>
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: