During the first few years of school, students begin applying the concept of parts and wholes; they work with halves, then quarters and eighths. Some students will only notice the number of parts, without realising the parts must be equal.

Even though these students might develop appropriate understandings like 'the larger the number of parts, the smaller the parts will be', the misconception that it is only the number of parts that define a fraction may persist.

When looking at a written fraction, students with this misconception interpret the denominator as indicating the number of parts, without realising the fraction label only applies if the parts are equal.