2003 AMC 10B Problem 12

Al, Betty, and Clare split \$1000 among them to be invested in different ways. Each begins with a different amount. At the end of one year, they have a total of \$1500. Betty and Clare have both doubled their money, whereas Al has managed to lose \$100. What was Al's original portion?

\textbf{(A) }250 \qquad\textbf{(B) } 350 \qquad\textbf{(C) }400\qquad\textbf{(D) } 450\qquad\textbf{(E) }\$500$

Full credit goes to MAA for authoring these problems. These problems were taken on the AOPS website.