Strategies for addition, subtraction, multiplication, and divisi

Strategies for addition, subtraction, multiplication, and division

What are we doing today?

Going over strategies

Don't know a math fact, no problem! We will discuss strategies for finding answers when you don't know the answer to addition, subtraction, multiplication or division problems. We have already discussed fact families, let's look at some new strategies.

Multiple Select

Which of the following problems can be solved by counting back?

• 7 - 3

• 8 + 2

• 4 + 3

• 10 - 3

Multiple Select

Which of the following problems can be solved by counting on?

• 7 - 3

• 8 + 2

• 4 + 3

• 10 - 3

Multiple Choice

Jamal has 12 marbles. His caretaker gives him 5 more. How many marbles does Jamal have now?

• 17

• 18

• 16

• 15

Multiple Choice

Sofia sees 14 butterflies in the garden. Then 6 more fly in. How many butterflies are there now?

• 21

• 19

• 20

• 18

Multiple Choice

Ethan had 17 blocks. He gave 8 to his friend. How many blocks does he have left?

• 10

• 9

• 8

• 11

An array is a way to organize objects into rows and columns so you can count them easily.

In 3 x 4 we can make 3 rows with 4 columns to see that there are 12 squares, meaning 3 x 4 = 12/

You can also think of this as how many groups can you make with the number you divide by. In 12/3 that would be how many groups of 3?

Multiple Select

Which questions can be solved with an array?

• 8x9

• 3x8

• 54/9

• 24/4

Multiple Select

Which questions can be solved with equal groups?

• 8x9

• 3x8

• 54/9

• 24/4

Match

Match each question with the array that shows the answer

• 4 x 5 = 20

• 3 x 6 = 18

• 7 x 2 = 14

• 8 x 1 = 8

• 5 x 5 = 25

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Match

Match each question with the equal groups that shows the answer

24/6 = 4

10/5 = 2

12/3 = 4

30/5 = 6

8/4 = 2

• 24/6 = 4

• 10/5 = 2

• 12/3 = 4

• 30/5 = 6

• 8/4 = 2

Multiple Choice

Solve using an array: What is 4 × 7?

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• 28

• 24

• 32

• 21

Multiple Choice

Solve using equal groups: 48 ÷ 8 = ?

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• 7

• 8

• 6

• 5

Multiple Choice

Solve using an array: What is 6 × 9?

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• 49

• 45

• 63

• 54

Multiple Choice

Solve using equal groups: 56 ÷ 7 = ?

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• 8

• 9

• 7

• 6