Today’s first puzzle concerns Zoom. For those of you who have been hiding under a stone all lockdown, it is a video-conferencing app.
1) Deduce the Zoom algorithm for placing four faces, using the three screengrabs below taken from three different people’s computers during the same meeting. For those who have never used Zoom before, the yellow outline tells you who is speaking, and doesn’t affect the positions. The fourth screengrab from the same meeting is above, but you can solve the problem without it.
I should have introduced you to my colleagues. Ben Lyttleton and I write the book series Football School, which uses football to get kids thinking and reading. Daisy is our brilliant editor and Laurelie our fantastic designer. (We’re working on a new book for September.)
A month ago I set four problems from Football School: The Ultimate Puzzle Book, the most recent book in the series. You seemed to really enjoy the puzzles, so here are two more.
2) Read the ten words below. If you were able to turn the screen upside down and read it in a mirror, only one of the words below will appear exactly the same. Can you work out which one?
BAR, BENCH, BOX, CIRCLE, DUG-OUT, GOAL, LINE, POST, SPOT, TURF.
3) The image below shows 22 positions of a ball as it moves around a pitch, joined by lines. The correct path of the ball starts at Q and then, moving only along the lines, passes through all the other letters, spelling out a phrase of seven English words. The path passes each letter once and only once. What’s the phrase?
The answer is quite hard but you can do it!
PLEASE NO SPOILERS. I’ll be back with the solutions at 5pm.
One final thing, for any parents, teachers or children reading. Football School and The Guardian have teamed up for the second annual Young Sportswriter of the Year competition, for children aged 7-12. Entrants must submit a match report or sports profile of no more than 600 words. There are some great prizes, such as a live online workshop with one of the Guardian’s top sportswriters, a £100 voucher and the complete set of Football Schools. If you love sport and dream of being a writer or commentator, this is the competition for you.
The judges include the former Germany defender and World Cup winner Per Mertesacker, the Aston Villa Women’s sporting director and former England forward Eni Aluko, Vic Marks, former cricketer for England and Somerset, and the golfer Georgia Hall, the 2018 British Open winner.
The deadline is July 3. All the relevant information is here. And if you need some ideas about what to write about, we wrote this story to help you get started. On your marks, get set, write!
I set a puzzle here every two weeks on a Monday. I’m always on the look-out for great puzzles. If you would like to suggest one, email me.
I first saw the Zoom puzzle on on Jenny Quinn’s Math in the Time of Corona blog. Jenny is president-elect of the Mathematical Association of America
If you are reading this in the Guardian app, and you want a notification each time I post a puzzle, or its solution, click the ‘Follow Alex Bellos’ button above.
Football School: the Ultimate Puzzle Book by Alex Bellos and Ben Lyttleton, illustrated by Spike Gerrell, is the eighth book in the Football School series, which aims to inspire reading and curiosity through football, and is packed with logic games, crosswords, riddles, spot the differences, and much more.
If you want more Football School, please join us every Friday at 10am UK on our YouTube channel, when we broadcast a live Football School class with lots of interactive activities for Key Stage 2 pupils.
