2004 AMC 12A Problem 15

Brenda and Sally run in opposite directions on a circular track, starting at diametrically opposite points. They first meet after Brenda has run 100 meters. They next meet after Sally has run 150 meters past their first meeting point. Each girl runs at a constant speed. What is the length of the track in meters?

\text {(A) }250 \qquad \text {(B) }300 \qquad \text {(C) }350 \qquad \text {(D) } 400\qquad \text {(E) }500

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