Classification of Fractions

Proper fractions

Proper fractions are those whose numerator is less than the denominator. Its overall value is between zero and one.


Improper Fractions

Improper fractions are those whose numerator is greater than the denominator. Its overall value is greater than one.


Mixed Number

The mixed number or mixed fraction is composed of a integer part and fraction.

To convert a mixed number to an improper fraction, the numerator becomes the sum of the product of the integer and the denominator plus the numerator. The denominator remains the same.


To convert an improper fraction to a mixed number, divide the numerator by the denominator. The quotient then becomes the integer of the mixed number and the remainder becomes the numerator of the fraction. The denominator remains the same.

nº mixto

Decimal fractions

The decimal fractions have as a denominator a power of 10.


Equivalent Fractions

Two fractions are equivalent when the product of its extremes is equal to the product of its middles.


a and d are the extremes; b and c, are the middles.

Determine whether the follwing fractions are equivalent:


4 · 12 = 6 · 8              48 = 48          Yes



If a fraction is multiplied by a fraction of an integer (a whole fraction) not including zero, the result is equivalent to the original fraction.

In the first case, it is called extended or amplified.


Simplifying fractions

Simplifying or reducing a fraction is transforming it into a simpler, equivalent fraction.

To simplify a fraction, divide the numerator and the denominator by the same number.

In order to determine what number to divide by, find the first prime numbers of both the numerator and denominator: 2, 3, 5, 7, ... In other words, try to divide the numerator and denominator by a number divisible by both.

The process is repeated until there is no more common divisors.

If the terms of the fraction end up in zeros, begin by removing the final common zeros of the numerator and denominator.

If the number for which the numerator and denominator are divided by is the greatest common divisor of both, an irreducible fraction is reached.


Irreducible fractions

The irreducible fractions are those that cannot be simplified any further. This happens when the numerator and denominator are both coprime.