The answer is 9/500, or 1.8%. The problem can be set up
algebraically. For each trip, there is a 100% chance that you will arrive in pod
A, B, or C. Let X be the chance that you arrive in pod A, & since it is
twice as likely that you will arrive in A than B, there is only half the chance
that you will arrive in B than A. So B is 1/2 X. By the same reasoning, there is
only 1/6 the chance you would arrive in C than A, so C is 1/6 X. The equation
thus looks like this: 100 = X + 1/2X + 1/6X. X=60, so A = 60, B = 30, & C =
10. These numbers correspond to the % chances you would arrive in each pod.