Subtract 15/30 from 21/49
21/49 - 15/30 is -1/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 49 and 30 is 1470
Next, find the equivalent fraction of both fractional numbers with denominator 1470 - For the 1st fraction, since 49 × 30 = 1470,
21/49 = 21 × 30/49 × 30 = 630/1470 - Likewise, for the 2nd fraction, since 30 × 49 = 1470,
15/30 = 15 × 49/30 × 49 = 735/1470 - Subtract the two like fractions:
630/1470 - 735/1470 = 630 - 735/1470 = -105/1470 - After reducing the fraction, the answer is -1/14
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/49-15/30 21/98-15/30 21/49-15/60 63/49-15/30 21/49-45/30 21/49-15/90 21/49-75/30