The Missing Dollar puzzle from Martin Gardner's Aha! Gotcha book series

Martin Gardner wrote Aha! Gotcha: Paradoxes to Puzzle and Delight and Aha! Insight in the early 1980s and I love them both. Both books have excellent brain teasers with charming illustrations. They are both out of print, which is criminal, but Amazon has used copies for $(removed) (plus $(removed) s&h).