Subtract 70/49 from 28/21
1st number: 1 7/21, 2nd number: 1 21/49
28/21 - 70/49 is -2/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 49 is 147
Next, find the equivalent fraction of both fractional numbers with denominator 147 - For the 1st fraction, since 21 × 7 = 147,
28/21 = 28 × 7/21 × 7 = 196/147 - Likewise, for the 2nd fraction, since 49 × 3 = 147,
70/49 = 70 × 3/49 × 3 = 210/147 - Subtract the two like fractions:
196/147 - 210/147 = 196 - 210/147 = -14/147 - After reducing the fraction, the answer is -2/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 56/21-70/49 28/42-70/49 28/21-70/98 84/21-70/49 28/63-70/49