Subtract 80/49 from 21/40
1st number: 21/40, 2nd number: 1 31/49
21/40 - 80/49 is -2171/1960.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 49 is 1960
Next, find the equivalent fraction of both fractional numbers with denominator 1960 - For the 1st fraction, since 40 × 49 = 1960,
21/40 = 21 × 49/40 × 49 = 1029/1960 - Likewise, for the 2nd fraction, since 49 × 40 = 1960,
80/49 = 80 × 40/49 × 40 = 3200/1960 - Subtract the two like fractions:
1029/1960 - 3200/1960 = 1029 - 3200/1960 = -2171/1960
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/40-80/49 21/80-80/49 21/40-80/98 63/40-80/49