Using derived facts to multiply mentally

Today we will use our knowledge of multiplying and dividing by 10, 100 and 1000 to derive facts from known facts. We will then use the distributive law and derived facts to multiply by choosing the most efficient and effective representations.

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.

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!

Question 1

Question 2

Question 3

Question 4

Question 5

Q1.The strategy of separating a number into its individual units of value is commonly known as?

1/5

Q2.Half of 24 is also the same as:

2/5

Q3.The bar model below is used to help divide or multiply numbers. What number should be placed in the top white boxes?

3/5

Q4.Which of the following number sentences will help you to solve the calculation 25 x 8?

4/5

Q5.Which derived fact helps me to mentally solve 240 ÷ 5?

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.

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!

Question 1

Question 2

Question 3

Question 4

Question 5

Q1.The strategy of separating a number into its individual units of value is commonly known as?

1/5

Q2.Half of 24 is also the same as:

2/5

Q3.The bar model below is used to help divide or multiply numbers. What number should be placed in the top white boxes?

3/5

Q4.Which of the following number sentences will help you to solve the calculation 25 x 8?

4/5

Q5.Which derived fact helps me to mentally solve 240 ÷ 5?

5/5

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.

Quiz:

Using Derived Facts to Multiply Mentally Quiz

We covered a wide range of strategies for mental arithmetic during the lesson today which will allow you to be flexible and efficient when faced with different problems and tasks. Now it is time to put your knowledge to the test! Remember to read all questions carefully.

Question 1

Question 2

Question 3

Question 4

Question 5

Q1.Which of the following methods for answering a multiplication questions is NOT a mental strategy?

1/5

Q2.Today we discussed distributive law in relation to multiplication. But which of the following number sentences does NOT correctly represent distributive law?

2/5

Q3.Which of the following representations would be efficient for the calculation 317 x 23?

3/5

Q4.For which of these calculations would you consider using a mental strategy and NOT a written method?

4/5

Q5.Which calculation do the dienes represent?

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.

Quiz:

Using Derived Facts to Multiply Mentally Quiz

We covered a wide range of strategies for mental arithmetic during the lesson today which will allow you to be flexible and efficient when faced with different problems and tasks. Now it is time to put your knowledge to the test! Remember to read all questions carefully.

Question 1

Question 2

Question 3

Question 4

Question 5

Q1.Which of the following methods for answering a multiplication questions is NOT a mental strategy?

1/5

Q2.Today we discussed distributive law in relation to multiplication. But which of the following number sentences does NOT correctly represent distributive law?

2/5

Q3.Which of the following representations would be efficient for the calculation 317 x 23?

3/5

Q4.For which of these calculations would you consider using a mental strategy and NOT a written method?

4/5

Q5.Which calculation do the dienes represent?

5/5

Lesson summary: Using derived facts to multiply mentally

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