This video explains how to find the nth triangular number. For a refresher on triangular numbers see our video: https://youtu.be/3G0VozmToZ4 Practice questions are at the end of the video. Skip to: 00:00 Introduction 00:25 How to find the nth triangular number 01:37 Formula for finding the nth triangular number 02:38 Practice questions

This video will explain how to find the area of a trapezium and provides a visual demonstration of the formula, using the area of a parallelogram. Skip to: 00:00 Introduction 00:17 What is a trapezium 00:43 Trapezium measurements 01:03 Visual demonstration of formula 01:56 Formula for area of a trapezium 02:06 Example 02:36 Practice questions

This video explains how to calculate upper and lower bounds when a number has been rounded. Practice questions and answers at the end of the video. Skip to: 00:00 Introduction 00:19 What are upper and lower bounds 01:02 Degree of accuracy 01:40 Examples 02:35 Practice questions

This video explains what the multiples and factors of a number are. Practice questions are at the end of the video.

This short video explains how to identify semi-regular tessellations: tessellations made up of two or more regular polygons. Practice questions are at the end of the video. For an explanation of regular tessellations, see our video: https://youtu.be/PiOa_vWKJA4 Skip to: 00:00 What are semi-regular tessellations 00:34 How to identify the pattern at the vertex 01:21 Practice questions

This video explains how to find the prime factors of a number using the factor tree method. Practice questions are at the end of the video.

This video will show you how to find the volume of a cuboid. Practice questions and answers are at the end of the video.

We explain how to find the lowest common multiple of two or more numbers, using two methods: listing the multiples and using prime factorisation. Practice questions and answers are at the end of the video.

This video explains two methods to find the highest common factor (also known as the greatest common factor) of two or more numbers: by listing the factors or by prime factorisation. For a refresher on multiples and factors: https://youtu.be/4EkhaETrcnY For a refresher on prime factors: https://youtu.be/1zagn5okZgM

This video explains what a scatter graph/plot is and how to plot them. A practice question is provided at the end of the video. Skip to: 00:00 Introduction 00:18 What is a scatter graph/scatter plot? 00:40 How to plot a scatter graph 01:41 Scatter graphs: practice question

This video explains how to find the lowest common multiple of two or more numbers, using two methods: listing the multiples and using prime factorisation. Practice questions and answers are at the end of the video. For a refresher on multiples: https://youtu.be/pEy8QKEBL_M For a refresher on prime factors: https://youtu.be/Bphq-n84ouM Skip to: 00:00 Intro 00:27 What does lowest common multiple mean 01:00 Method 1: Listing the multiples 01:29 Method 2: Using prime factorisation 01:54 Example 02:13 Practice questions and answers

This video will explain what decimal place value is and the different place value headings for decimal numbers, from thousands to thousandths. Practice questions and answers are at the end of the video. For an introduction on place value, check out our video What Is Place Value: https://youtu.be/BL6pGhnBdj8 Skip to: 00:00 Introduction 00:20 Place value recap 00:50 Decimal place value headings 02:00 Decimal place value chart/grid 02:58 Place value practice questions

This video will explain what place value is and the different place value headings from units to thousands. Practice questions and answers are at the end of the video. (Decimals and beyond thousands will be explained in another video).

This video walks you through some GCSE exam style practice questions on the topic of substitution in maths.

This video explains substitution in maths within the topic of algebra and what it means to evaluate an expression. Practice questions are at the end of the video.

This video explains some of the most common symbols used in mathematics, their names and their meanings.

This video goes through some important mathematical keywords in algebra. A matching activity is at the end of the video.

This updated video will explain how to find the circumference of a circle when given either the diameter or the radius. We also explain you how the formula is actually derived. Have a go at the practice questions at the end of the video.

This video explores the fraction wall; a visual representation of fractions. We look at three fraction walls for: fractions, decimals and percentages.

This video explains how to find the area of a triangle when we are given the lengths of the base and vertical height. We also explain why the formula works. Practice questions and answers are at the end of the video.