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How Long Does it Take?

Age 7 to 11
Challenge Level Yellow star
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Margaux from St Thomas More's Catholic Primary School managed to complete it.

Vihaan from KHPS King Henry VIII School wrote:

How long does it take to brush your teeth? One of my strategies is to start from the middle then do the four corners.  After that I fill in the gaps from the edges.

Another one is doing the outside square then doing the inside square. With my strategy I scored 320 and none were by luck or next to each other. The first time playing against the clock the time was 0.44. The second time against the clock it was 0.52. The third time against the clock it was 0.54.

Freddy from Pickhurst wrote the following and showed the screen he got:

When I was playing this game the first thing that I did was choose a random card, read it, work out the answer, memorise what was written on the card and then remember where the card was. I did that every turn and matched up the cards.

You may also like

Times

Which times on a digital clock have a line of symmetry? Which look the same upside-down? You might like to try this investigation and find out!

Clock Hands

This investigation explores using different shapes as the hands of the clock. What things occur as the the hands move.

Ten Green Bottles

Do you know the rhyme about ten green bottles hanging on a wall? If the first bottle fell at ten past five and the others fell down at 5 minute intervals, what time would the last bottle fall down?

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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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