Today Puzzle #530
Puzzle No. 530 鈥� Wednesday 24 July
Four cards are on the table labelled A, B, 1 and 2. The cards all have a number on one side and a letter on the other. A rule is proposed: A card with a consonant on it always has an even number on the other side of the card. Which two cards do you need to turn over to prove this rule is true?
Today’s #PuzzleForToday has been set by Kit Yates is an author, maths communicator and Senior Lecturer in mathematical biology at the University of Bath.
Click here for the answer
You need to turn over the B and the 1. You need to turn over the B to check there is an even number on the other side and the 1 to make sure there is not a consonant on the other side. You don’t need to turn over the A because there’s nothing in the statement which restricts what can be on the other side of a vowel card. Similarly you don’t need to turn over the 2 because there’s nothing in the statement which restricts what can be on the other side of even card. Odd cards however, must not have a consonant on the other side so you do need to check the 1.
-
![]()
Puzzle for Today 鈥� Index
Find all of the currently available Puzzles for Today, with answers.
More fiendish brain-teasers and quizzes on 大象传媒 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...
