Topic Six (1.6): Approximations
Introduction
In today’s lesson, we will look at how we can round numbers to one significant figure to help approximate (estimate) the answer to a calculation.
Warm Up
First complete the skill checker on page 45.
Working through your course book
- Start by watching this video, which shows how rounding to one significant figure can be used to estimate an answer to a multiplication question:
WATCH – Estimating Answers - Multiplication (MathsWatch) Links to an external site.
- Read and make notes on pages 45-46, copying out the worked example.
- Now see if you can answer the Band 2 questions on pages 46-47.
- If you would like more practice, then work through these lessons on the MyMaths website:
EXPLORE – Estimating calculations (MyMaths) Links to an external site.
- You may also want to watch the following Corbettmaths video:
Plenary
You have a choice: you can end this lesson by playing a maths game, or watching a video (or even both, if you have time!)
Game-time!
Is your estimating quick enough to Beat the Clock? Play the game on slide 6:
PLAY – Estimating calculations (MyMaths) Links to an external site.
Video
When a news article reports the size of a crowd, have they really counted every single person?
WATCH – Counting Crowds (Twig) [Not available on Sample course]
Support activities for this topic
The Band 1 questions on page 46 will help build your skills on this topic.
Extension activities for this topic
If you would like more of a challenge on this topic, go to pages 47-48 and attempt the Band 3 questions.