Subtract 70/18 from 10/21
1st number: 10/21, 2nd number: 3 16/18
10/21 - 70/18 is -215/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
10/21 = 10 × 6/21 × 6 = 60/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
70/18 = 70 × 7/18 × 7 = 490/126 - Subtract the two like fractions:
60/126 - 490/126 = 60 - 490/126 = -430/126 - After reducing the fraction, the answer is -215/63
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 20/21-70/18 10/42-70/18 10/21-70/36 30/21-70/18 10/63-70/18 10/21-70/54 50/21-70/18 10/21-70/90 70/21-70/18