Definition
Decimal fraction
A decimal fraction has 10, 100, 1,000, and so on as its denominator.
What it means
The denominator tells which decimal place to use. Tenths have denominator 10, hundredths have 100, and thousandths have 1,000. Put the numerator into those place-value positions to write the matching decimal.
Remember it
Power-of-ten denominator, ready for decimal places.
Example
The fraction 43/100 means 43 hundredths, so 43/100 = 0.43. The 4 is in the tenths place and the 3 is in the hundredths place.
Watch for
The fraction 3/4 is not a decimal fraction in that form because 4 is not a power of ten, although 3/4 = 75/100, which is a decimal fraction.
Common mix-up
A decimal fraction is written as a fraction such as 43/100; its decimal notation is 0.43.
Exact meaning
In a decimal fraction, the denominator is 10 multiplied by itself one or more times; this structure maps directly to decimal places.