Subtract 30/7 from 12/21
1st number: 12/21, 2nd number: 4 2/7
12/21 - 30/7 is -26/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
12/21 = 12 × 1/21 × 1 = 12/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
30/7 = 30 × 3/7 × 3 = 90/21 - Subtract the two like fractions:
12/21 - 90/21 = 12 - 90/21 = -78/21 - After reducing the fraction, the answer is -26/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/21-30/7 12/21-60/7 12/42-30/7 12/21-30/14 36/21-30/7 12/21-90/7 12/63-30/7 12/21-30/21 60/21-30/7 12/21-30/35 84/21-30/7 12/21-30/49