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  • Early Years Foundation Stage

Oh! Harry!

Age 7 to 11
Challenge Level Yellow starYellow star
Primary curriculum
  • Problem
  • Getting Started
  • Student Solutions
  • Teachers' Resources

A group of eight children in Class 6 were measuring water using measuring cylinders. They coloured the water to make reading the scales easier.

They lined up the cylinders in two neat rows, each labelled with a child's name and the amount they had measured out.

Then Harry opened the window and the wind blew most of the labels onto the floor! "Oh! Harry!" they all wailed. Can you relabel the cylinders for them?

measuring cylinders

Ahmed had measured out just a thousand millilitres and Belinda twice as much as Ahmed.

Grace had measured out three-quarters of the amount that Belinda had done and Freddie had half the amount that Ahmed had measured out.

Which were their cylinders?

Callum had coloured his water blue. How much did he measure out?

Ellie had coloured her water pink and Dan coloured his orange. How much did they measure out?

"Don't drink that!" Harry had laughed, pointing at Dan's cylinder, "It's not orange juice!" As his hand stretched out he knocked over his red liquid. "Oh! Harry!" they all wailed again.

How much was left in Harry's cylinder after the accident?


You can download a resource sheet of the measuring cylinders.

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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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