A sum of money at simple interest amounts to Rs. 815 in 3 years and to Rs. 894 in 4 years. The sum is:  Answers.
A) s. 650  B) s. 690  C) s. 698  D) s. 700  E) s. 578
S.I. for 1 year = Rs. (894 - 815) = Rs. 79.   S.I. for 3 years = Rs.(79 x 3) = Rs. 237.   Principal = Rs. (815 - 237) = Rs. 578.   Answer: Option s. 578
<result>E</result>
A sum of money at simple interest amounts to Rs. 815 in 3 years and to Rs. 894 in 4 years. The sum is: