Mathematics · Glossary

What is Decimal places?

Also known as: decimal number

Definition 29.1 Primary & Middle School Mathematics · Chapter 29 — Decimal Numbers

After the decimal point come the tenths, the hundredths, the thousandths — each worth ten times less than the one before:

4.362=4+310+6100+21000=43621000.4.362 = 4 + \frac{3}{10} + \frac{6}{100} + \frac{2}{1000} = \frac{4\,362}{1000}.
The place-value table of 4.362: whole part in blue, decimal part in red, the point between units and tenths.
The place-value table of 4.3624.362: whole part in blue, decimal part in red, the point between units and tenths.
Zooming on the number line: the stretch from 4.3 to 4.4, magnified, is itself cut into ten hundredths — and 4.362 sits just past 4.36.
Zooming on the number line: the stretch from 4.34.3 to 4.44.4, magnified, is itself cut into ten hundredths — and 4.3624.362 sits just past 4.364.36.

Examples

Example 29.2 (Many readings, one number)

4.3624.362 can be read “four point three six two”, or “four and 362362 thousandths”, or decomposed as 4+0.3+0.06+0.0024 + 0.3 + 0.06 + 0.002. And padding with final zeros changes nothing: 4.362=4.36204.362 = 4.3620. But 4.3624.03624.362 \neq 4.0362: a zero inside pushes every digit to a smaller place.

Example 29.3 (Where is it on the line?)

To place 4.3624.362: between 44 and 55; zooming, between 4.34.3 and 4.44.4; zooming again, between 4.364.36 and 4.374.37, closer to 4.364.36. Each decimal digit is one more level of zoom.

Read in context →
Definition 38.1 Primary & Middle School Mathematics · Chapter 38 — Decimal Numbers

A decimal number has a whole part and a decimal part, separated by the decimal point. Each place to the right of the point is worth ten times less than the one before: tenths, hundredths, thousandths. For instance

13.407=13+410+0100+71000=1×10+3+4×110+7×11000.13.407 = 13 + \frac{4}{10} + \frac{0}{100} + \frac{7}{1000} = 1 \times 10 + 3 + 4 \times \frac{1}{10} + 7 \times \frac{1}{1000}.
The place-value table of 13.407: the decimal point sits between the units and the tenths.
The place-value table of 13.40713.407: the decimal point sits between the units and the tenths.
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