Answers

Subtract 21/81 from 84/70

1^st number: 1 14/70, 2^nd number: 21/81

84/70 - 21/81 is 127/135.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 70 and 81 is 5670
   
   Next, find the equivalent fraction of both fractional numbers with denominator 5670
2. For the 1st fraction, since 70 × 81 = 5670,
   84/70 = 84 × 81/70 × 81 = 6804/5670
3. Likewise, for the 2nd fraction, since 81 × 70 = 5670,
   21/81 = 21 × 70/81 × 70 = 1470/5670
4. Subtract the two like fractions:
   6804/5670 - 1470/5670 = 6804 - 1470/5670 = 5334/5670
5. After reducing the fraction, the answer is 127/135

MathStep (Works offline)

Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad

Related: ⁸⁴/₇₀-⁴²/₈₁ ⁸⁴/₇₀-⁶³/₈₁

Subtract Fractions Calculator