Fractions and decimals are two different ways of writing a portion of a number; you can write any fraction as a decimal and vice versa. You can write the term “one quarter” as a fraction with numbers and convert it to its equivalent decimal. When you write a term like one quarter out as a fraction, the words tell you what numbers to put in the fraction: If you divide an object into quarters or fourths, it’s the same as dividing it into four equal parts. If you have one-quarter of an object, you have one of its four equal parts, so those numbers – one and four – go into your fraction.
Write Out the Numerator
Write the first part of the term “one quarter.” That first part of the term – one – becomes the numerator, or top number, in your fraction. So you have:
? is just the placeholder for the denominator or bottom number of the fraction, which you'll fill in during the next step.
Write Out the Denominator
Write the second part of the your fraction term as the denominator of the fraction. In this case the fraction term is "one quarter," but it could also be read as "one fourth." Either way, the number that goes on the bottom of the fraction is 4, giving you:
Note that the denominator of the fraction represents the number parts you've divided something into (say, cutting a cake into four giant pieces), and the numerator of the fraction tells you have many of those parts you have. In this case, you have one out of four pieces or one quarter of the total.
Convert the Fraction to a Decimal
Divide the fraction’s numerator by the denominator to convert the fraction to a decimal. To continue this example, you have:
1/4 = 1 ÷ 4 = .25
TL;DR (Too Long; Didn't Read)
You can apply these steps to convert any fraction written in words, such as three-fourths or five-sevenths, to a decimal.