Unit 3 Math Review

EM4 Unit 3
Math Review: 3rd Grade

Objectives

• I can review strategies and skills taught in unit 3.

• I can apply strategies I learned to addition and subtraction problems.

• I can demonstrate my learning by completing some practice problems.

• Look at the input and output numbers.

• Check to see what rule the numbers follow.

• Make sure to think about your different operations: addition, subtraction, division and multiplication.

• The rule MUST apply to all numbers

Function Machines: Input and Output

3-1: What's My Rule

Multiple Choice

What number comes next?

3, 7, 11, 15, 19...

• 23

• 24

• 22

• 21

Multiple Choice

What number is next?

2, 4. 6, 8...

• 16

• 10

• 12

• 0

• Find closer but easier numbers by rounding your numbers in the original problem.

• Round to the nearest 10 or 100.

• Look to see what operation the problem is having you do.

• Find the estimated sum or difference.

Rounding Numbers and Estimating

3-2: Estimating

Multiple Choice

Round 83 to the Nearest 10

• 85

• 90

• 80

• 100

Multiple Choice

Round 49 to the nearest 10.

• 0

• 100

• 40

• 50

Partial Sums

3-3 and 3-4: Addition Strategies

Column Addition

Multiple Choice

Find the Sum.

12 + 6 = ?

• 18

• 20

• 6

Multiple Choice

Find the Sum.

8 + 9 = ?

• 15

• 16

• 17

Counting-Up Subtraction

3-5 and 3-6: Subtraction Strategies

Expand-and-Trade Subtraction

Multiple Choice

What's the difference?

17 - 6 = ?

• 23

• 9

• 11

Multiple Choice

What's the difference?

12- 8 = ?

• 20

• 4

• 2

3-7 and 3-8: Pictographs

3-9 and 3-10: Multiplication

Multiplication Square Facts

Commutative Property of Multiplication

• Both factors are the same.

• The array created is a square.

• The factors are flipped.

• The product is the same.

• The array created is flipped over.

Multiple Choice

Is the following fact a multiplication square?

5 x 5 = 25

• Yes

• NO

Multiple Choice

Is the following fact a multiplication square?

7 x 5 = 35

• Yes

• NO

3-11 and 3-12: Multiplication

Adding a Group

Subtracting a Group

• Start with a helper fact.

• Add a group or two to figure out the product of the unknown fact.

• Helper Fact: 5 x 7= 35

• Unknown Fact: 6 x 7 = ?

• Start with a helper fact.

• Add a group or two to figure out the product of the unknown fact.

• Helper fact: 10 x 4 = 40

• Unknown Fact: 9 x 4 = ?

3-13: Equivalent Names

Name Collection Boxes

• Write in expressions that total the number given.

• Write down words, pictures or number models that fit.

Any Questions?

Math test is tomorrow. Make sure you're prepared.