Subtract 21/84 from 7/45
7/45 - 21/84 is -17/180.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 84 is 1260
Next, find the equivalent fraction of both fractional numbers with denominator 1260 - For the 1st fraction, since 45 × 28 = 1260,
7/45 = 7 × 28/45 × 28 = 196/1260 - Likewise, for the 2nd fraction, since 84 × 15 = 1260,
21/84 = 21 × 15/84 × 15 = 315/1260 - Subtract the two like fractions:
196/1260 - 315/1260 = 196 - 315/1260 = -119/1260 - After reducing the fraction, the answer is -17/180
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 14/45-21/84 7/45-42/84 7/90-21/84 21/45-21/84 7/45-63/84 35/45-21/84 49/45-21/84