A fraction is a part of something. For example, when you cut a pie in to four equal pieces then each piece is one-fourth of the pie. If you eat two of those pieces, then you have eaten half of the pie. (3-page lesson)
This is a whole circle.
It is one whole or one or 1.
We have all of the circle. It is 100% of the circle.
One-fourth can be written as 1/4.
We cut the circle into four equal parts.
One of those equal parts is one-fourth. It is 25%.