Today Puzzle #622
Puzzle No. 622 鈥� Friday 29 November
A prime number is only divisible by itself and one. Today's date in short form is 29/11/19 - three prime numbers. How many times will this happen this century?
Today’s #PuzzleForToday has been set by Kyle Evans an award winning maths communicator and director of maths at Barton Peveril College
Click here for the answer
1300. There are 25 prime numbers under 100, so this phenomenon will only occur in years ending in 02, 03, 05, 07, 11, 13, 17, 19, 23, 29, 31, 37, 41, 43, 47, 53, 59, 61, 67, 71, 73, 79, 83, 89, 97. In these years there will be nine 'triple prime' dates in February, ten in November and eleven in March, May and July, so 52 per year. 25 x 52 = 1300.
(Note, if you thought 1 was a prime number, you would have got the answer 1794)
-
![]()
Puzzle for Today 鈥� Index
Find all of the currently available Puzzles for Today, with answers.
More fiendish brain-teasers and quizzes on 麻豆官网首页入口 Radio...
-
![]()
From autumn leaves to the magic roundabout: test yourself with our favourite quizzes.
-
![]()
We asked the intelligence agency to set our listeners a code-cracking challenge... Can you solve it?
-
![]()
Quiz: How many of these Mastermind music questions can you answer?
Here's a chance to find out whether your specialist subject on Mastermind could be the entire history of music.
-
![]()
Six conundrums to grapple with, including the Riddle of the Sphinx. Try not to forfeit your life...
