Subtract 70/42 from 10/21
1st number: 10/21, 2nd number: 1 28/42
10/21 - 70/42 is -25/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 42 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 21 × 2 = 42,
10/21 = 10 × 2/21 × 2 = 20/42 - Likewise, for the 2nd fraction, since 42 × 1 = 42,
70/42 = 70 × 1/42 × 1 = 70/42 - Subtract the two like fractions:
20/42 - 70/42 = 20 - 70/42 = -50/42 - After reducing the fraction, the answer is -25/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 20/21-70/42 10/42-70/42 10/21-70/84 30/21-70/42 10/63-70/42 50/21-70/42 70/21-70/42