If Rs.10 be allowed as true discount on a bill of Rs.110 due at the end of a certain time,then the discount allowed on the same sum due at the end of double the time is : Choose the correct choice from the following answers:
A) Rs. 20
B) Rs. 21.81
C) Rs. 22
D) Rs. 18.33
E) None of these
Solution   S.I. on Rs.(110 -10) for a certain time =Rs.10.   S.I. on Rs. 100 for double the time =Rs. 20.   T.D. on Rs. 120 =Rs.(120 -100)=Rs. 20.   T.D. on Rs. 110 =Rs.left ( 20/120x120 ) =Rs.18.33.   Answer Rs. 18.33
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If Rs.10 be allowed as true discount on a bill of Rs.110 due at the end of a certain time,then the discount allowed on the same sum due at the end of double the time is :