RaghavKhanna
Total amount invested = $100,000
Stocks = S
Bonds = 100,000 - S
Statement 1:Amount of stocks diverted to bonds = 0.75S
Amount of bonds diverted to stocks = (100,000 - S)*0.75 = 75000 - 0.75S
Amount of stocks = 0.25S + 75000 - 0.75S
And,
Amount of bonds = 25000
+ 0.25S + 0.75S
You have a sign error in your analysis of Statement 1 (it should be a minus, not a plus), when computing the bond value, and there's a similar error in Statement 2 (you divided 100,000 by 4 instead of 2 and also flipped a sign). Conceptually speaking, using either Statement, it must be possible that S = B, because we're doing identical things to both investments and ending up with equal amounts, so any solution that proves S has a unique value different from $50,000 cannot be right. The only question we need to answer is whether it's also possible that S and B are unequal, i.e. whether it's possible S can take on other values besides $50,000.
From Statement 1, if he plans to invest $S in stock and $B in bonds, then when he transfers 3/4 of his stock investment to bonds, he'll be investing only $S/4 in stock. But then he adds to that 3/4 of his bond investment, so he adds to that $3B/4. So if he changes his plans as per Statement 1, he'll be investing S/4 + 3B/4 in stock, and similarly will be investing B/4 + 3S/4 in bonds. If these are equal we get this equation:
S/4 + 3B/4 = B/4 + 3S/4
B = S
from which we know S = $50,000.
From Statement 2, transfering half of each investment to the other, the new investment in stock becomes S/2 + B/2, and the new investment in bonds becomes B/2 + S/2. Those are obviously equal no matter what, so S and B can be anything, and Statement 2 gives us no information. So the answer is A.
I object to the wording of Statement 1 though. Solving, we find that he plans to invest $50,000 in stocks and $50,000 in bonds. We then learn that if he "changes his plans" he will be investing $50,000 in stocks and $50,000 in bonds. That is not a change from his previous plans.