You may also like

Three Squares

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

Two Dice

Find all the numbers that can be made by adding the dots on two dice.

Biscuit Decorations

Andrew decorated 20 biscuits to take to a party. He lined them up and put icing on every second biscuit and different decorations on other biscuits. How many biscuits weren't decorated?

One Big Triangle

Age 5 to 7
Challenge Level


Here are nine triangles.  Each one has three numbers on it.

 

Your challenge is to arrange these triangles to make one big triangle, so the numbers that touch add up to 10.

You can print out this copy of the triangles and cut them out, then try arranging them.  
If you prefer, here is a printable version of the triangles with the numbers represented on tens frames.

Let us know how you go about trying to make the big triangle.
How did you get started?
What did you do next?

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.
Copyright © 1997 - 2021. University of Cambridge. All rights reserved.
NRICH is part of the family of activities in the Millennium Mathematics Project.