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Science, Technology, Engineering and Mathematics
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Challenge from Westdene Primary, Brighton
Stage: 2 and 3
Tom Kimber, a teacher at Westdene Primary School in Brighton emailed us to say:
I am a MaST teacher who was lucky enough to be at one of your recent NRICH events in London. I got into a really interesting mathematical discussion with some very advanced pupils in my class about the pattern of the units column in numbers-to-the-power-of.
Anyway, after a long and convoluted journey through many different mathematical areas, it has reached a concluding* question. I thought I'd share it with you as my children have ENJOYED getting their teeth into it:
Look at this calculation:
$7^x + 9^y =$
I get a random number generator to generate two random whole numbers. The first one it generates I place in position $x$. The second number it generates I put at position $y$. What is the probability that, when I complete the calculation $7^x + 9^y =$, I will get a number that is a multiple of $10$ as my answer?
Hope you find it as interesting as we are!
* - I say concluding... probably not!
Meet the team
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. More information on many of our other activities can be found here.
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