A sum of money lent out at S.I. amounts to Rs. 720 after 2 years and to Rs. 1020 after a further period of 5 years. The sum is?  Select the correct option.
A) 776
B) 267
C) 269
D) 600
E) 298
S.I for 5 years = (1020 - 720)   = Rs. 300.   S.I. for 2 years = 300/5 * 2   = Rs. 120.   Principal = (720 - 120)   = Rs.600.   Answer: 600
<result>D</result>
A sum of money lent out at S.I. amounts to Rs. 720 after 2 years and to Rs. 1020 after a further period of 5 years. The sum is?