Applying mental calculation strategies to adding and subtracting decimals

In this lesson, we will use a range of informal mental strategies to add and subtract decimal numbers.

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Quiz:

Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Q1.True or False: 1.356 - 0.999 = 0.356

1/4

Q2.True or false: 134.76 - 82.5 = 52.76

2/4

Q3.True or false: 24.56 - 19.9 = 4.66

3/4

Q4.True or false: 46.78 - 3.8 = 42.99

4/4

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
Quiz:

Intro quiz - Recap from previous lesson

Before we start this lesson, let’s see what you can remember from this topic. Here’s a quick quiz!

Q1.True or False: 1.356 - 0.999 = 0.356

1/4

Q2.True or false: 134.76 - 82.5 = 52.76

2/4

Q3.True or false: 24.56 - 19.9 = 4.66

3/4

Q4.True or false: 46.78 - 3.8 = 42.99

4/4

Video

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Worksheet

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This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
Quiz:

Applying mental calculation strategies when adding and subtracting decimals

Fantastic work finishing today's lesson! Put your mental strategies to the test and solve these decimal equations.

Q1.6.3 + 12.27

1/6

Q2.2.89 - 1.41 =

2/6

Q3.7.3 + 7.2 =

3/6

Q4.2.671 + 5.999

4/6

Q5.4.53 - 4.49

5/6

Q6.1.82 + 4.08

6/6

This quiz includes images that don't have any alt text - please contact your teacher who should be able to help you with an audio description.

Unit quizzes are being retired in August 2023

Why we're removing unit quizzes from the website >
Quiz:

Applying mental calculation strategies when adding and subtracting decimals

Fantastic work finishing today's lesson! Put your mental strategies to the test and solve these decimal equations.

Q1.6.3 + 12.27

1/6

Q2.2.89 - 1.41 =

2/6

Q3.7.3 + 7.2 =

3/6

Q4.2.671 + 5.999

4/6

Q5.4.53 - 4.49

5/6

Q6.1.82 + 4.08

6/6

Lesson summary: Applying mental calculation strategies to adding and subtracting decimals

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