Two fractions can be subtracted if they have common denominators. While subtracting fractions, we need to subtract the numerators. If the denominators are different, we can still subtract them by converting the denominators of the two fractions into a common denominator.
Subtracting Fractions with like Denominators

Step 1: Subtract the numerators and put them over denominator.

Step 2: If necessary, simplify the fraction into simplest form.
                       Subtracting Fractions Like Denominator

Subtracting Fractions with unlike Denominators

Step 1: Multiply numerator of each fraction with the denominator of other fraction. Then, subtract them.

Step 2: Multiply denominators of both the fractions together.

Step 3: Simplify the fraction.

                         Subtracting Fractions Unlike-Denominator