Decimal Place Value Review

Decimal Place Value Review

What is place value?

The numerical value that a digit has depending on it's position in a number

Example: the number 2 in 27.593 is in the TENS place, 7 is in the ONES place, 5 is in the TENTHS place, 9 is in the HUNDREDTHS place, and 3 is in the THOUSANDTHS place

Place value can be represented in different ways...

It can be represented using base 10 blocks, or on a number line

(see next slides for examples and visuals)

Base 10 blocks can represent different place values (as seen in the previous pictures)

1 whole is represented by 1 or 1.0

1 tenth is represented by .1 or 0.1

1 hundredth is represented by .01 or 0.01

Can you fill in the missing numbers on the number line? (do this on a sheet of paper)

Multiple Choice

What place value does the 8 in 3.586 represent?

• tens

• thousandths

• hundredths

• tenths

Multiple Choice

What place value does the 5 in 65.709 represent?

• tenths

• hundreds

• ones

• thousands

Multiple Choice

What place value does the 4 in 3.694 represent?

• hundreths

• thousands

• tens

• thousandths

Remember Kiran's number line? Her model does not correctly represent 0.08. Draw a number line on a piece of paper and correctly represent 0.08 on the number line

Multiple Choice

How much does 0.08 represent?

• One tenth

• One whole

• One hundredth

• One thousandth

Depending on it's place value and which side of the decimal the number is on, numbers are either getting bigger or smaller

whole numbers (decimal) fractions

Numbers to the right / Numbers to the left

right = get smaller

left = get bigger

Multiple Choice

Let's compare...which number is bigger? 0.04 or 0.004?

• 0.04

• 0.004

Multiple Choice

Which number is bigger? 0.026 or 0.25

• 0.026

• 0.25

Multiple Choice

Which number is smaller? 0.044 or 0.012

• 0.044

• 0.012

We can also compare two decimals using greater than, less than, and equal to signs

<

>

=

Multiple Choice

Which statement is correct?

• 0.1 > 00.1

• 0.1 = 00.1

• 0.1 < 00.1

Multiple Choice

Which statement is correct?

• 42.03 > 4.203

• 42.03 < 4.203

• 42.03 = 4.203

Multiple Choice

Which statement is correct?

• 0.006 > 0.600

• 0.006 = 0.600

• 0.006 < 0.600

Decimals can also be represented in expanded form and word form

Let's look at some examples....

The number 2.671 can be written in expanded form:

2 x 1 + 6 x 0.1 + 7 x 0.01 + 1 x 0.001

The number 62.438 can written in expanded form:

6 x 10 + 2 x 1 + 4 x 0.1 + 3 x 0.01 + 8 x 0.001

The number 8.163 can be written in word form:

eight and one hundred sixty-three thousandths

Now you try!

Decimals can be written in expanded form using fractions as well

Example:

0.1 is the same as 1/10

0.01 is the same as 1/100

0.001 is the same as 1/1,000

You finished! Great job!!