A sum of money lent out at S.I. amounts to a total of $600 after 2 years and to $850 after a further period of 5 years. What was the initial sum of money that was invested?
Choose the correct choice:
A) $ 500	B) $ 520	C) $ 540	D) $ 560	E) $ 580

Rationale: s . i for 5 years = $ 850 - $ 600 = $ 250 the s . i . is $ 50 / year s . i . for 2 years = $ 100 principal = $ 600 - $ 100 = $ 500 the answer is a .
Answer: A