Strategies to Multiply with Multiples of Ten

MAFS.3.NBT.1.3

Lesson OpeningName the following numbers:

1.3 tens2.36 ones3.14 tens4.2 hundreds

Lesson OpeningName the following numbers:

1.3 tens = 302.36 ones = 363.14 tens = 1404.2 hundreds= 200

I can use base-ten blocks, a number line, or place value to model and record

multiplication with multiples of 10.

Multiples of 10 are…

10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110…

I can use base-ten blocks, a number line, or place value to model and record

multiplication with multiples of 10.

Multiples of 10 are…

10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110…

What do all the multiples of 10 have in common?

I can use base-ten blocks, a number line, or place value to model and record

multiplication with multiples of 10.

1 ten1 x 1 ten1 X 10 = 10

4 tens4 x 1 ten4 X 10 = 40

7 tens7 x 1 ten7 X 10 = 70

I can use base-ten blocks, a number line, or place value to model and record

multiplication with multiples of 10.

5 x 301 jump of 30

I can use base-ten blocks, a number line, or place value to model and record

multiplication with multiples of 10.

5 x 302 jumps of 30

I can use base-ten blocks, a number line, or place value to multiply with multiples of 10.

5 x 303 jumps of 30

I can use base-ten blocks, a number line, or place value to model and record

multiplication with multiples of 10.

5 x 304 jumps of 30

I can use base-ten blocks, a number line, or place value to model and record

multiplication with multiples of 10.

5 x 305 jumps of 30

So, 5 x 30 = 150

I can use base-ten blocks, a number line, or place value to model and record

multiplication with multiples of 10.3 x 40

I can use base-ten blocks, a number line, or place value to model and record

multiplication with multiples of 10.3 x 40

Think: 3 x 4 tens = 12 tens

12 tens = 120

Susanne cut a length of string 30 inches long. Vanessa cut a length of string 6 times as long as Susanne’s.

How long was Vanessa’s string?

I can use base-ten blocks, a number line, or place value to model and record

multiplication with multiples of 10.

Susanne cut a length of string 30 inches long. Vanessa cut a length of string 6 times

as long as Susanne’s. How long was Vanessa’s string?

Model 6 times 30 with base-ten blocks.

I can use base-ten blocks, a number line, or place value to model and record

multiplication with multiples of 10.

Susanne cut a length of string 30 inches long. Vanessa cut a length of string 6 times

as long as Susanne’s. How long was Vanessa’s string?

Model 6 times 30 with base-ten blocks.

30 X 6

I can use base-ten blocks, a number line, or place value to model and record

multiplication with multiples of 10.

Susanne cut a length of string 30 inches long. Vanessa cut a length of string 6 times

as long as Susanne’s. How long was Vanessa’s string?

Model 6 times 30 with base-ten blocks.

30 X 6 Multiply the

ones.

I can use base-ten blocks, a number line, or place value to model and record

multiplication with multiples of 10.

Susanne cut a length of string 30 inches long. Vanessa cut a length of string 6 times

as long as Susanne’s. How long was Vanessa’s string?

Model 6 times 30 with base-ten blocks.

30 X 6 Multiply the ones. 0 (there are no ones)

I can use base-ten blocks, a number line, or place value to model and record

multiplication with multiples of 10.

Susanne cut a length of string 30 inches long. Vanessa cut a length of string 6 times

as long as Susanne’s. How long was Vanessa’s string?

Model 6 times 30 with base-ten blocks.Combine the tens.

30 X 6 Multiply the ones. 0

I can use base-ten blocks, a number line, or place value to model and record

multiplication with multiples of 10.

Susanne cut a length of string 30 inches long. Vanessa cut a length of string 6 times

as long as Susanne’s. How long was Vanessa’s string?

Model 6 times 30 with base-ten blocks.Combine the tens.

Ten tens is 1 hundred.

30 X 6 Multiply the ones. 0

I can use base-ten blocks, a number line, or place value to model and record

multiplication with multiples of 10.

Susanne cut a length of string 30 inches long. Vanessa cut a length of string 6 times

as long as Susanne’s. How long was Vanessa’s string?

Model 6 times 30 with base-ten blocks.18 tens = 1 hundred 8 tens = 180

30 X 6 180 (1 hundred, 8 tens)

I can use base-ten blocks, a number line, or place value to model and record

multiplication with multiples of 10.

Susanne cut a length of string 30 inches long. Vanessa cut a length of string 6 times

as long as Susanne’s. How long was Vanessa’s string?

Vanessa’s string was 180 inches long.

I can use base-ten blocks, a number line, or place value to model and record

multiplication with multiples of 10.

Your Turn

1)5 × 30 =2)30 × 9 =3)4 × 60 =4)7 × 90 =5)8 × 80 =6)9 × 60 =

Think 5 × 3 tens = 15 tens

Think 3 tens × 9 = 27 tens

Think 4 × 6 tens = 24 tens

Think 7 × 9 tens = 63 tens

Think 8 × 8 tens = 64 tens

Think 9 × 6 tens = 54 tens

= 150 = 270 = 240 = 630 = 640 = 540

Bonus QuestionDoes 3 × 90 have the same value as 9 × 30? How do

you know?

Can you think of other problems like this?

Exit Ticket and Bonus Questions

1) Ms. Young gets 8 boxes of pencils for her class. Each box of pencils contains 60 pencils. How many pencils did Ms. Young get?

2) When Ms. Young went to pay for the pencils, the cashier told her there was a sale: For every 3 boxes of pencils you buy, you get one box free. If Ms. Young left the store with 8 boxes of pencils, how many boxes of pencils were free for Ms. Young?

3) If each box of pencils cost $4, how much did Ms. Young spend on pencils?

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