DECIMAL PLACE VALUE

Unit 1: Lesson 3

Place Value Chart• A place value chart is divided into periods: billions,

millions, thousands, and ones.• Each period is divided into 3 columns: hundreds, tens,

and ones.• A decimal separates the whole numbers from the decimal

numbers.• Example:

Billions Millions Thousands Ones • Tenths Hundredths Thousandths Ten Thousandths

H T O H T O H T O H T O

Identifying the Decimal Place of Digits:

1. Use the place value chart to fill in the number (Remember: Only place 1 number in each column.)

2. Identify the column the digit is in.

Examples:

What place is the 6 in the number 23.643?

What place is the 5 in the number 0.985?

Billions Millions Thousands Ones • Tenths Hundredths Thousandths Ten Thousandths

H T O H T O H T O H T O

Identifying the Decimal Place of Digits:

• Trick: – Place a 1 under the decimal – Place 0’s under each of the following numbers.– Add ths to the number to get the place

• Example: What place is the 3 in the number 56.7893?

10000

The 3 is in the ten thousandths place!

Identifying the Decimal Place of Digits:

• Examples:– What place is the 4 in the number 12.456?– What place is the 2 in the number 156.8278?– What place is the 7 in the number 57.894?– What place is the 8 in the number 615.6583?– What place is the 1 in the number 513.987?– What place is the 5 in the number 1.6785?

Answers:– What place is the 4 in the number 12.456?

Tenths– What place is the 2 in the number 156.8278?

Hundredths– What place is the 7 in the number 57.894?

Ones– What place is the 8 in the number 615.6583?

Thousandths– What place is the 1 in the number 513.987?

Tens– What place is the 5 in the number 1.6785?

Ten Thousandths

Identifying the Value of Decimals:

1. Write the number that is underlined.

2. Fill all spaces to the LEFT of the digit with zeros. (Don’t forget the decimal!)

3. Omit all numbers to the RIGHT.

Identifying the Value of Decimals:

• Examples:

• What is the value of the underlined digit?

• 23.643

• 0.985

• 12.548

• 70.1256

• 96.3547

Identifying the Value of Decimals:

• Answers:

• What is the value of the underlined digit?

• 23.643 0.6

• 0.985 0.005

• 12.548 0.5

• 70.1256 0.0006

• 96.3547 0.05

Reading Decimals:

• The decimal represents the word AND• When reading decimals, read the number

and the column of the last digit• HINT: Cover up the decimal and read the

number in front. Then read AND and the number behind the decimal and the place of the last digit.– Example: 0.043 read as forty three thousandths– Example: 0.65 read as sixty five hundredths– Example: 6.7 read as six and seven tenths

Reading Decimals

– Example: 22.789Twenty two and seven hundred eighty nine thousandths

– Example: 17.54Seventeen and fifty four hundredths

– Example: 1,456.009One thousand four hundred fifty six and nine thousandths

– Example: 245.87Two hundred forty five and eighty seven hundredths

– Example: 17.9Seventeen and nine tenths

Writing Decimals

• When writing decimals in standard form, the last number must be in the place value stated.

• It may be necessary to add zeros in all other columns in order to hold the place of the digit.

• HINT: Cover up “and” and all words behind it. Write the number in front. Then identify the place that the last digit should be in and write the last number. Fill in all other numbers and add zeros if needed.

Writing Decimals

• Examples:

• Fourteen and three tenths

14.3

• Four and seven hundredths

4.07

• Ninety-three thousandths

0.093

Writing Decimals

• Two thousand six and four thousandths

2,006.004

• Five hundred eight one and six ten-thousandths

581.0006

• Twelve thousand four and twenty one hundredths

12,004.21

Equivalent Decimals

• Equivalent means equal

• Steps to writing equivalent decimals:– Write the number exactly.– Add one or more zeros to the END of the

number (Adding zeros to the end of a decimal number does not change the value of the number)

Equivalent Decimals

• Examples:– 0.765

– 12.43

– 7.869

– 1,456.009