Two ordering constraints at once

The letters A, B, C, D, E are arranged in a uniformly random order. What is the probability that A appears before B and D appears before E? Give a decimal to four places.

Show hints (2)+
  1. Each pair's order is 50-50 by symmetry — value them separately.
  2. The pairs share no letters, so the two events are independent: multiply.

Answer

Reveal answer →

0.25

Want the full step-by-step worked solution? It's part of Premium — along with a worked solution for every question in the bank.

Asked at: SIG, Two Sigma

Related questions