Answers

Subtract 21/81 from 35/70

35/70 - 21/81 is 13/54.

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,
   35/70 = 35 × 81/70 × 81 = 2835/5670
3. Likewise, for the 2nd fraction, since 81 × 70 = 5670,
   21/81 = 21 × 70/81 × 70 = 1470/5670
4. Subtract the two like fractions:
   2835/5670 - 1470/5670 = 2835 - 1470/5670 = 1365/5670
5. After reducing the fraction, the answer is 13/54

MathStep (Works offline)

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

Related: ³⁵/₇₀-⁴²/₈₁ ³⁵/₇₀-⁶³/₈₁

Subtract Fractions Calculator