Multiple choice general knowledge math & puzzles 16, 25, 36, 72, 144, 196, 225 36 72 196 225 Reveal answer Fill a bubble to check yourself B Correct answer Explanation The series contains perfect squares: 16=4², 25=5², 36=6², 144=12², 196=14², 225=15². However 72 is not a perfect square (8.485² ≈ 72). All other numbers are perfect squares, making 72 the odd one out.