Subtract 28/21 from 12/56
1st number: 12/56, 2nd number: 1 7/21
12/56 - 28/21 is -47/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 56 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 56 × 3 = 168,
12/56 = 12 × 3/56 × 3 = 36/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
28/21 = 28 × 8/21 × 8 = 224/168 - Subtract the two like fractions:
36/168 - 224/168 = 36 - 224/168 = -188/168 - After reducing the fraction, the answer is -47/42
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/56-28/21 12/56-56/21 12/56-28/42 36/56-28/21 12/56-84/21 12/56-28/63 60/56-28/21 84/56-28/21