Inga invested part of her $6000 savings in common stock and the rest in rare stamps. At the end of the year, she realized a gain of 9% on the stock and 12% on the stamps. If her savings now amounts to $6615, how much did she invest in stamps?

Answer 1

Let x be the amount Inga invested in rare stamps.
Inga earned a 9% gain on the stock, so she earned 6000 * 9% = $<<6000*9*.01=540>>540 from the stock.
Inga earned a 12% gain on the stamps, so she earned x * 12% = 0.12x from the stamps.
In total, Inga earned 540 + 0.12x = $6615.
Thus, the total amount Inga invested in stamps is x = $<<6615-540=6075>>6075. Answer: \boxed{6075}.