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Age range: 7-11
Duration: 30-59 mins
  • Maths

Triangular numbers

This maths activity uses triangular numbers to calculate the number of gifts in the 12 days of Christmas.

In this fun Christmas activity for kids, students will learn about triangular numbers and how, when a number sequence is added together, they can be drawn to make triangles as dots.

This resource focuses on the calculation of triangular numbers using the staircase method and the formula to calculate any triangular number. This festive activity will help students learn how to have fun with maths.

Join Wilf Wonders and his brother, Tom, as they walk you through how to do this activity at home or in school this Christmas and a free activity sheet can be downloaded below.

Oh ho ho, and please do share your maths highlights with us @IETeducation! #SantaLovesSTEM

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How to calculate triangular numbers

Wonderful Wilf calculates the 12 days of Christmas presents using triangular numbers

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