A certain sum of money at simple interest amounted Rs.840 in 10 years at 3% per annum, find the sum?	Choose one.
A) 287
B) 276
C) 279
D) 646
E) 370
840 = P [1 + (10*3)/100]   P = 646   Answer: 646
<result>D</result>
A certain sum of money at simple interest amounted Rs.840 in 10 years at 3% per annum, find the sum?