Subtract 12/21 from 5/15
5/15 - 12/21 is -5/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 15 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 15 × 7 = 105,
5/15 = 5 × 7/15 × 7 = 35/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
12/21 = 12 × 5/21 × 5 = 60/105 - Subtract the two like fractions:
35/105 - 60/105 = 35 - 60/105 = -25/105 - After reducing the fraction, the answer is -5/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 10/15-12/21 5/15-24/21 5/30-12/21 5/15-12/42 5/15-36/21 5/45-12/21 5/15-12/63 25/15-12/21 5/15-60/21 5/75-12/21 35/15-12/21 5/15-84/21