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Planet Plex Time

Age 5 to 7
Challenge Level Yellow star
  • Problem
  • Getting Started
  • Student Solutions
  • Teachers' Resources

Maziyar from Sir Roger Manwoods School and Rachel from Histon and Impington Infant School both sent completely correct solutions to Planet Plex Time. Maziyar says:

School starts at one 'o' clock.

He'll be about two get up two hours later.
He was about to go to sleep 5 hours earlier.
It is 9 hours before school finishes on Friday.

Rachel explains how she worked out the final part:

I worked this out by saying that 1 hour later he gets up on Thursday; 2 hours later he goes to school on Thursday; 3 hours later he has lunch on Thursday; 4 hours later, he plays on Thursday; 5 hours later he has dinner on Thursday; 6 hours later he goes to sleep on Thursday; 7 hours later he gets up on Friday; 8 hours later he goes to school on Friday and 9 hours later he finishes school, and is about to have lunch.

Well done both of you.

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Calendars were one of the earliest calculating devices developed by civilizations. Find out about the Mayan calendar in this article.

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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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