Subtract 70/21 from 8/18
1st number: 8/18, 2nd number: 3 7/21
8/18 - 70/21 is -26/9.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 18 and 21 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 18 × 7 = 126,
8/18 = 8 × 7/18 × 7 = 56/126 - Likewise, for the 2nd fraction, since 21 × 6 = 126,
70/21 = 70 × 6/21 × 6 = 420/126 - Subtract the two like fractions:
56/126 - 420/126 = 56 - 420/126 = -364/126 - After reducing the fraction, the answer is -26/9
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 16/18-70/21 8/36-70/21 8/18-70/42 24/18-70/21 8/54-70/21 8/18-70/63 40/18-70/21 8/90-70/21 56/18-70/21