# Writing and Naming Decimals

### Learning Outcomes

- Name a decimal number
- Given the name of a decimal number, write it in decimal notation

Counting number | Name |
---|---|

[latex]1[/latex] | One |

[latex]10=10[/latex] | Ten |

[latex]10\cdot 10=100[/latex] | One hundred |

[latex]10\cdot 10\cdot 10=1000[/latex] | One thousand |

[latex]10\cdot 10\cdot 10\cdot 10=10,000[/latex] | Ten thousand |

Decimal | Fraction | Name |
---|---|---|

[latex]0.1[/latex] | [latex]{\Large\frac{1}{10}}[/latex] | One tenth |

[latex]0.01[/latex] | [latex]{\Large\frac{1}{100}}[/latex] | One hundredth |

[latex]0.001[/latex] | [latex]{\Large\frac{1}{1,000}}[/latex] | One thousandth |

[latex]0.0001[/latex] | [latex]{\Large\frac{1}{10,000}}[/latex] | One ten-thousandth |

*ten thousand*. Likewise, the names of the decimal places correspond to their fraction values. Notice how the place value names in the first table relate to the names of the fractions from the second table. This chart illustrates place values to the left and right of the decimal point. Notice two important facts shown in the tables.

- The "th" at the end of the name means the number is a fraction. "One thousand" is a number larger than one, but "one thousandth" is a number smaller than one.
- The tenths place is the first place to the right of the decimal, but the tens place is two places to the left of the decimal.

*five dollars and three cents*. Naming decimals (those that don’t represent money) is done in a similar way. We read the number [latex]5.03[/latex] as

*five and three hundredths*. We sometimes need to translate a number written in decimal notation into words. As shown in the image below, we write the amount on a check in both words and numbers. When we write a check, we write the amount as a decimal number as well as in words. The bank looks at the check to make sure both numbers match. This helps prevent errors.

Let’s try naming a decimal, such as [latex]15.68[/latex]. | |

We start by naming the number to the left of the decimal. | fifteen______ |

We use the word "and" to indicate the decimal point. | fifteen and_____ |

Then we name the number to the right of the decimal point as if it were a whole number. | fifteen and sixty-eight_____ |

Last, name the decimal place of the last digit. | fifteen and sixty-eight hundredths |

*fifteen and sixty-eight hundredths*.

### Name a decimal number.

- Name the number to the left of the decimal point.
- Write "and" for the decimal point.
- Name the "number" part to the right of the decimal point as if it were a whole number.
- Name the decimal place of the last digit.

### Exercises

Name each decimal: 1. [latex]4.3[/latex] 2. [latex]2.45[/latex] 3. [latex]0.009[/latex] 4. [latex]-15.571[/latex] Solution1. | |

[latex]4.3[/latex] | |

Name the number to the left of the decimal point. | four_____ |

Write "and" for the decimal point. | four and_____ |

Name the number to the right of the decimal point as if it were a whole number. | four and three_____ |

Name the decimal place of the last digit. | four and three tenths |

2. | |

[latex]2.45[/latex] | |

Name the number to the left of the decimal point. | two_____ |

Write "and" for the decimal point. | two and_____ |

Name the number to the right of the decimal point as if it were a whole number. | two and forty-five_____ |

Name the decimal place of the last digit. | two and forty-five hundredths |

3. | |

[latex]0.009[/latex] | |

Name the number to the left of the decimal point. | Zero is the number to the left of the decimal; it is not included in the name. |

Name the number to the right of the decimal point as if it were a whole number. | nine_____ |

Name the decimal place of the last digit. | nine thousandths |

4. | |

[latex]-15.571[/latex] | |

Name the number to the left of the decimal point. | negative fifteen |

Write "and" for the decimal point. | negative fifteen and_____ |

Name the number to the right of the decimal point as if it were a whole number. | negative fifteen and five hundred seventy-one_____ |

Name the decimal place of the last digit. | negative fifteen and five hundred seventy-one thousandths |

### TRY It

[ohm_question]146224[/ohm_question] [ohm_question]146225[/ohm_question] [ohm_question]146568[/ohm_question] [ohm_question]146569[/ohm_question]### example

1. Write the number six and seventeen hundredths:six and seventeen hundredths | |

The word and tells us to place a decimal point. |
___.___ |

The word before and is the whole number; write it to the left of the decimal point. |
[latex]6[/latex]._____ |

The decimal part is seventeen hundredths. Mark two places to the right of the decimal point for hundredths. | [latex]6[/latex]._ _ |

Write the numerals for seventeen in the places marked. | [latex]6.17[/latex] |

Answer: Solution

fourteen and thirty-seven hundredths | |

Place a decimal point under the word ‘and’. | ______. _________ |

Translate the words before ‘and’ into the whole number and place it to the left of the decimal point. | [latex]14[/latex]. _________ |

Mark two places to the right of the decimal point for "hundredths". | [latex]14[/latex].__ __ |

Translate the words after "and" and write the number to the right of the decimal point. | [latex]14.37[/latex] |

Fourteen and thirty-seven hundredths is written [latex]14.37[/latex]. |

### try it

[ohm_question]146570[/ohm_question]### Write a decimal number from its name.

- Look for the word "and"—it locates the decimal point.
- Mark the number of decimal places needed to the right of the decimal point by noting the place value indicated by the last word.
- Place a decimal point under the word "and." Translate the words before "and" into the whole number and place it to the left of the decimal point.
- If there is no "and," write a "0" with a decimal point to its right.

- Translate the words after "and" into the number to the right of the decimal point. Write the number in the spaces—putting the final digit in the last place.
- Fill in zeros for place holders as needed.

### example

Write twenty-four thousandths as a decimal.Answer: Solution

twenty-four thousandths | |

Look for the word "and". | There is no "and" so start with 0 [latex]0[/latex]. |

To the right of the decimal point, put three decimal places for thousandths. | |

Write the number [latex]24[/latex] with the [latex]4[/latex] in the thousandths place. | |

Put zeros as placeholders in the remaining decimal places. | [latex]0.024[/latex] |

So, twenty-four thousandths is written [latex]0.024[/latex] |

### try it

[ohm_question]146571[/ohm_question] [ohm_question]146572[/ohm_question][latex]\begin{array}{cccc}5=5.0\hfill & & & -2=-2.0\hfill \\ 5=5.00\hfill & & & -2=-2.00\hfill \\ 5=5.000\hfill & & & -2=-2.000\hfill \end{array}[/latex] and so on [latex]\dots[/latex]

## Licenses & Attributions

### CC licensed content, Original

- Question ID 146571, 146572, 146568,146569, 146224, 146225.
**Authored by:**Lumen Learning.**License:**CC BY: Attribution.

### CC licensed content, Shared previously

- Read and Write Decimals.
**Authored by:**James Sousa (Mathispower4u.com).**License:**CC BY: Attribution. - Examples: Write a Number in Decimal Notation from Words.
**Authored by:**James Sousa (Mathispower4u.com).**License:**CC BY: Attribution.

### CC licensed content, Specific attribution

- Prealgebra.
**Provided by:**OpenStax**License:**CC BY: Attribution.**License terms:**Download for free at http://cnx.org/contents/[email protected].