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  • Early Years Foundation Stage

Times

Age 7 to 11
Challenge Level Yellow star
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Even though this challenge is about times on clocks, the display on a calculator will help you to explore the patterns more easily than trying to write the numbers on paper. So grab a calculator and punch in some "times". A little hand mirror can help check for symmetry and reflections too.

Let us know what you find  by emailing primary.nrich@maths.org! Please don't worry that your solution is not "complete" - we'd like to hear about anything you have tried. Teachers - you might like to send in a summary of your children's work.

Hurrah! In 2015 we had a solution come in from Jake at St George's C of E primary school
Times
You have to have 1 at the start otherwise it won't work.
Then when I started to think about it, I realised you could have 0 or 2 to start. You can't have a number greater than 2 because it is a 24 hour clock.
If you used 8 (which has symmetry) you would have 18:81 and you can't have 8 in the minutes as the highest number you can have is 59 in the minutes.
I then worked out you could have these times:

0 1:1 0
02:50
05:20's good
1 0:0 1
1 1 . 1 1
1 2:5 1
1 5:2 1
20:05
2 1:1 5
22:55  Jake

Thanks, that's a good answer, sorry your previous submission got lost in the airways.

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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