Eureka Math Module 1

Module 1 Lesson 12

by April Morgan

I can multiply decimals by whole numbers and use estimation skills to determine the reasonableness of my answer.​

Fill in the Blanks

Use an Area Model to solve 31 X 4 

  

Fill in the Blanks

Use an Area Model to solve 3.1 X 4

Fill in the Blanks

Use an Area Model to solve .31 X 4

​Look at the products of the last 3 problems:

124 12.4 1.24

​

What do you see?

​

Do these numbers have the same value?

​

Can you explain a multiplying strategy that would let me multiply first and then put the decimal in after?

5.1 X 6 =

What is the smallest unit being multiplied?

​

How can we turn 5.1 into tenths?

​

What would our new multiplication problem be if we 

write 5.1 as tenths?

Multiple Choice

What would our new multiplication problem be if we 

write 5.1 as tenths?

• 51 x 6

• 51 tenths X 6

• 5.1 x 6

• 0.51 x 6

Fill in the Blanks

5.1 X 6 =

​11.4 X 4 =

​

What is the smallest unit we are multiplying?

​

What would 11.4 look like changed into tenths?

Multiple Choice

What would 11.4 look like changed into tenths?

• 1.14 hundredths

• 11.4 tenths

• 1.14

• 114 tenths

Fill in the Blanks

11.4 X 4

Multiple Choice

3.12 X 4

 What place value would I put 3.12  in to help me solve?

• ones

• thousandths

• hundredths

• tenths

Fill in the Blanks

3.12 X 4

Fill in the Blanks

3.42 X 6 =

Multiple Choice

0.733 X 4 =

Which of these answers is the most reasonable?

• 2.932

• 29.32

• 293.2

• 2932

Multiple Choice

10.733 X 4 =

1 0 7 3 3  thousandths

  X        4

4 2 9 3 2   thousandths

Which of these answers is the most reasonable?

• 4.2932

• 42.932

• 429.32

• 4293.2

Open Ended

​What trick can I use to help me understand where to place my decimals when I am multiplying by decimals?