AMC 12 2004a 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?

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