Today Puzzle #788
Puzzle No. 788鈥� Wednesday 22 July 2020
July 22 is celebrated as Pi Approximation Day as the date written as 22/7 is an approximation of the mathematical constant Pi of 3.14. To celebrate, 6 times Olympic champion Sir Chris Hoy rides his unicycle with wheel diameter 50cm. On Hoy's first unicycle trip, his wheel makes 20 revolutions. Using the 22/7 approximation to pi, can you help Susan & Bobby work out far Sir Chris Hoy travelled in metres?
Today's #PuzzleForToday has been set by Bobby Seagull and fellow maths teacher Susan Okereke, who are both co-hosts of the Maths Appeal podcast.
Click here for the answer
The distance travelled through one full revolution of the wheel is equivalent to the circumference of the wheel.
Circumference = pi x diameter
= 22/7 x 1/2
=22/14 metres
20 revolutions = 20 x 22/14 = 440/14 =220/7 = 10 x pi
= 31.43m
-
![]()
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...
