Subtract 21/20 from 25/45
1st number: 25/45, 2nd number: 1 1/20
25/45 - 21/20 is -89/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 20 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 45 × 4 = 180,
25/45 = 25 × 4/45 × 4 = 100/180 - Likewise, for the 2nd fraction, since 20 × 9 = 180,
21/20 = 21 × 9/20 × 9 = 189/180 - Subtract the two like fractions:
100/180 - 189/180 = 100 - 189/180 = -89/180
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 50/45-21/20 25/45-42/20 25/90-21/20 25/45-21/40 75/45-21/20 25/45-63/20 25/45-21/60