Using round and adjust strategies to subtract and add near doubles

In this lesson, we will use round and adjust strategies to subtract and add near doubles. We will partition two digit numbers in order to make calculations easier.

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

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Quiz:

Using round and adjust strategies to add and subtract near doubles

Don’t worry if you get a question wrong! Forgetting is an important step in learning. We will recap next lesson.

Q1.Using round and adjust and mental strategies, 34 + 35 =

1/5

Q2.Using round and adjust and mental strategies, 42+ 46 =

2/5

Q3.Using round and adjust and mental strategies, 29 + 28 =

3/5

Q4.Using round and adjust and mental strategies, 35 + 39=

4/5

Q5.Using round and adjust and mental strategies, 49 + 47 =

5/5

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:

Using round and adjust strategies to add and subtract near doubles

Don’t worry if you get a question wrong! Forgetting is an important step in learning. We will recap next lesson.

Q1.Using round and adjust and mental strategies, 34 + 35 =

1/5

Q2.Using round and adjust and mental strategies, 42+ 46 =

2/5

Q3.Using round and adjust and mental strategies, 29 + 28 =

3/5

Q4.Using round and adjust and mental strategies, 35 + 39=

4/5

Q5.Using round and adjust and mental strategies, 49 + 47 =

5/5

Lesson summary: Using round and adjust strategies to subtract and add near doubles

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