Sum of fractions with different denominators


To find the difference of two unlike fraction.

Pre-requisite Knowledge

  • Concept of subtraction of natural numbers.
  • Concept of fractions.
  • Concept of grid method.

What is Fraction?

A fraction is a numerical value that represents the parts of the whole.

Parts of a Fraction

A fraction consists of two parts, namely the numerator and the denominator. The upper part of the fraction is called the numerator and the lower part of the fraction is called the denominator. For example, 4/7 is a fraction. Here, 4 is the numerator and 7 is the denominator.

Unlike fraction

  • Fractions with the different denominators are called unlike fractions.
  • Thus, 1/5, 2/7, 3/2, 8/6 are all unlike fractions.

Grid representation of fraction

We can represent a fraction numerator/denominator by letting a rectangular grid consisting of denominator stand for one whole and then numerator stand for the part of one whole.