A invested $300 in a business after 6 months B invested $200 in the business. End of the year if they got $100 as profit. Find A shares?  Choose the correct choice from the following options:	A) $ 100	B) $ 75	C) $ 20	D) $ 120	E) $ 50

Rationale: "a : b = 300 * 12 : 200 * 6 a : b = 3 : 1 a ' s share = 100 * 3 / 4 = $ 75 answer is b"
Answer: B