2, 3, and 4-Digit Multiplication by 1-digit Numbers

2, 3, and 4-Digit Multiplication by 1-digit Numbers

Chapter 2 Review/Test

Comparison Problems

Reggie has 12 times as many model cars as Jackson. Jackson has 5 model cars. Which equation shows how many cars Reggie has.

A. 5 x 12 = ?

B. 5 + 12 = ?

C. 12 – 5 = ?

D. 12 ÷ 5 = ?

Maria’s dog weighs 6 times as much as her rabbit. Together the pets weigh 56 pounds. What does Maria’s dog weigh?

Multiple Choice

Allison picked 4 times as many daisies as tulips. She picked a total of 20 flowers. How many daisies did she pick?

• 4

• 5

• 12

• 16

Multiple Choice

Which of the following equations represents the

comparison sentence?

56 is 7 times as many as 8

• 56 = 7 + 8

• 56 = 7 x 8

• 56 = 7 - 8

• 56 x 7 = 8

Multiply by Tens, Hundreds, & Thousands

To multiply by tens' hundreds, and thousands, you multiply the basic fact and then put the same numbers of zeros as the factors have

Example: 34 x 1,000 = 34,000

Multiple Choice

123 x 100 =

• 123,000

• 12,300

• 123

• 1,230

Multiple Choice

Last year a business had profits of $8,000.

This year its profits are 5 times as great.

What are this year’s profits?

• 4,000

• 40,000

• 400

• 400,000

Multiple Choice

60 x 10 =

• 600

• 60

• 6,000

• 6

Estimate Products

To estimate, round the greater factor to the greatest place value, and then multiply

Multiple Choice

Why do you estimate before you multiply?

• because rounding is easier

• to find the answer

• so you will know what a reasonable answer should be

• because I don't know how to multiply good

Multiple Choice

Estimate 46 x 7

• 40 x 7 = 280

• 50 x 7 = 350

• 46 x 7 = 322

• 4 x 7 = 28

The Distributive Property

...whatever's outside the parentheses has to be multiplied with everything inside the parentheses

Example: 7 x 23 = 7 x (20+3)

= (7x20) + (7x3)

=140 + 21

=161

Multiple Choice

How can 4(3 +9) be expressed using the distributive property?

• 4(3) + 4(4 + 9)

• 4(3) + 4(9)

• 4 + 9 = 9 + 4

• (4 + 3) x (4 + 9)

Expanded Form

...the value of each digit

Multiple Choice

Write 7,432 in expanded form.

• 1000 + 1000 +1000 + 432

• 7,000 + 400 + 30 +2

• 7,000 + 300 + 40 + 2

• 7 + 4 + 3 + 2

Partial Products

the parts that are added together to get the whole answer

Multiple Choice

What are the partial products?

1 82

× 6

_____

600

480

+12

_____

• 600

• 1,092

• 182

• 600, 480, and 12

Multiply 2, 3, and 4-Digit Numbers with Regrouping

Fill in the Blank

When multiplying by a 1-digit number, always begin in the ___________ place.

Examples:

1. 32 x 7

2. 543 x 4

Multiple Choice

Ms. Nicholson is buying 2 new chromebooks for the classroom. The price of each chromebook is $259. What is the total price of the chromebooks?

• $408

• $418

• $508

• $518

Multiple Choice

If Mr. James runs 8 miles a day. How many

miles will she run in 4 weeks?

• 32

• 28

• 56

• 224

Poll

Did you enjoy this review/test?

• Yes!

• No!