1. Chapter 1 / Whole Numbers and Introduction to Algebra
Decimal Notation
Chapter 1 / Whole Numbers and Introduction to Algebra
Like fractional notation, decimal notation is used to denote a part of a whole. Numbers written in decimal notation are called decimal numbers, or simply decimals. The decimal has three parts.
16.743
Whole number part
Decimal part
Decimal point

2. Place Value 1 Notice that the value of each place is 10
of the value of the place to its left.

3. Place Value
The position of each digit in a number determines its place value.
hundred-thousandths
hundreds
tens
tenths
hundredths
thousandths
ten-thousandths
ones 1 10 1
1000 1
100,000
Place Value
100 10 1 1
100 1
10,000
decimal point

4. Place Value 16.734 The digit 3 is in the hundredths place, so
its value is 3 hundredths or 3
100

5. Writing a Decimal in Words
Chapter 1 / Whole Numbers and Introduction to Algebra
Step 1: Write the whole number part in words.
Step 2: Write “and” for the decimal point.
Step 3: Write the decimal part in words as though it were a whole number, followed by the place value of the last digit.

6. Writing a Decimal in Words
Write the decimal in words.
whole number part
decimal part
one hundred forty-three
and
fifty-six thousandths

7. Writing Decimals in Standard Form
A decimal written in words can be written in standard form by reversing the procedure.
Write one hundred six and five hundredths in standard form.
one hundred six and five hundredths
whole-number part
decimal
decimal part
5 must be in the
hundredths place
106 . 05

8. Helpful Hint
When writing a decimal from words to decimal notation, make sure the last digit is in the correct place by inserting 0s after the decimal point if necessary.
For example,
three and fifty-four thousandths is 3.054
thousandths place