Multiple choice general knowledge math & puzzles Select odd one out... 29th February 2000 31st June 1999 29th April 1998 31st August 1997 Reveal answer Fill a bubble to check yourself B Correct answer Explanation June has only 30 days, so '31st June' is a non-existent date. February 2000 was a leap year (29 days), April 1998 has 30 days (so 29th is valid), and August always has 31 days. The impossibility of the date makes it the odd one out.