Subtract 21/81 from 42/35
1st number: 1 7/35, 2nd number: 21/81
42/35 - 21/81 is 127/135.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 81 is 2835
Next, find the equivalent fraction of both fractional numbers with denominator 2835 - For the 1st fraction, since 35 × 81 = 2835,
42/35 = 42 × 81/35 × 81 = 3402/2835 - Likewise, for the 2nd fraction, since 81 × 35 = 2835,
21/81 = 21 × 35/81 × 35 = 735/2835 - Subtract the two like fractions:
3402/2835 - 735/2835 = 3402 - 735/2835 = 2667/2835 - 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: 84/35-21/81 42/35-42/81 42/70-21/81 42/35-63/81