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Get Started Now- Intro Lesson: a9:32
- Intro Lesson: b9:10
- Intro Lesson: c3:29
- Lesson: 1a1:30
- Lesson: 1b1:06
- Lesson: 1c5:50
- Lesson: 2a1:53
- Lesson: 2b1:07
- Lesson: 2c0:50
- Lesson: 2d1:26
- Lesson: 2e0:48
- Lesson: 2f1:25
- Lesson: 3a2:41
- Lesson: 3b2:28
- Lesson: 4a3:26
- Lesson: 4b2:53
- Lesson: 52:08

In this lesson, we will learn:

- What are powers of 10?
- How to move the decimal place when multiplying decimals by powers of 10
- How to understand decimal multiplication using base ten (block) models

- All
**place values**are related to their neighboring**place values**by a. A__factor of 10__**place value**is__10 times more__than the place to its right and__10 times less__than the place to its left. - Each place value can be represented as a
__power of ten__

- Recall:
__repeated addition__becomes**multiplication**, ex. 10 + 10 + 10 = 3 ×10 __Repeated multiplication__becomes**powers**(or**exponents**), ex. 10×10×10 = 10^{3}- You can see that the
**exponent**is the same as the**number of zeroes**represented

- What happens when you multiply by
**powers of ten**? - When you multiply any number by 1, it stays
__exactly the same__! - What happens when you multiply by 10? 100? 1000?

- You can use the
**number of zeroes**as the number of places that a decimal must__jump to the right__when multiplying by**powers of ten**. - If you run out of numbers when moving the decimal
**to the right**, fill those spaces with**trailing zeroes**! - We can also use
to__base ten (block) models__**multiply**decimals with**powers of 10**. There are two different models, depending on what represents__one whole__: - If one whole is represented by a
**hundred block**(square): ex. multiplying 5 tens blocks by 10 will give you 5 wholes. - If one whole is represented by a
**thousand cube**: ex. multiplying 3 ones blocks by 100 will give you 3/10 wholes (or 3 tenths).

× 10 = 50 tens = 5 wholes =

$\large\square \, \square \,\square \,$ × 100 = 3 hundreds = 3/10 wholes =

- IntroductionIntroduction to multiplying decimals by powers of 10:a)What are powers of 10?b)What patterns can we see when using powers of 10 to multiply decimals?c)How can we use base ten (block) models to show decimal multiplication with powers of 10?
- 1.
**Multiplying decimals by powers of 10 by moving the decimal**

Multiply:a)2.993 × 10 =?b)100 × 0.05 =?c)2.8 × 1000 =? - 2.
**Multiplying decimals by powers of 10 by filling in the blanks**

Fill in the missing number in the following questions:a)_____ × 0.408 = 408b)_____ × 10 = 93.25c)0.017 × _____ = 0.17d)1000 × _____ = 4280e)_____ × 0.56 = 56f)_____ × 100 = 6.1 - 3.
**Using**__HUNDREDTHS__block models for decimal multiplication by powers of 10

If one whole is represented by a hundred block (big square made out of 100 tiny squares), then a tenth is represented by a stick (of 10 tiny squares). 10 tenths will make one whole, and 100 hundredths will make one whole.

Show the following multiplication statements using base ten block models, and solve:a)0.7 × 10 =?b)0.32 × 100 =? - 4.
**Using**__THOUSANDTHS__block models for decimal multiplication by powers of 10

If one whole is represented by a thousand cube (cube made out of 10 hundred blocks/plates; 1000 tiny squares), then a tenth is represented by a hundred block (plate of 100 tiny squares). 10 hundred blocks will make one whole, and 1000 thousandths will make one whole.

Show the following multiplication statements using base ten block models, and solve:a)0.004 × 1000 =?b)0.158 × 100 =? - 5.
**Word problem for decimal multiplication by powers of 10**

If the price of reusable metal drinking straws is $0.29 each when buying them straight from the factory, how much would it cost to buy 1000 metal straws in bulk?

Write out the multiplication statement and solve.

10.

Decimals

10.1

What are decimals?

10.2

Multiplying decimals by powers of 10

10.3

Dividing decimals by powers of 10

10.4

Coverting between decimals and fractions

10.5

Comparing and ordering decimals and fractions

10.6

Multiplying decimals with integers

10.7

Dividing decimals with integers

10.8

Word problems for decimals and integers