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Change Around

Age 5 to 7
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"This was fun," we heard from many people who moved the circles around as they tried to find out how to rebuild the triangle so it faced in the opposite direction. Gerrit did very well to put into words what you needed to do:

"To change the triangle's direction with only three moves, move the outside bottom row balls to the second row from the top, and move the top ball to the bottom."

Easy when you know how!


You may also like

Four Triangles Puzzle

Cut four triangles from a square as shown in the picture. How many different shapes can you make by fitting the four triangles back together?

Three Squares

What is the greatest number of squares you can make by overlapping three squares?

A City of Towers

In this town, houses are built with one room for each person. There are some families of seven people living in the town. In how many different ways can they build their houses?

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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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