Subtract 30/8 from 21/9
1st number: 2 3/9, 2nd number: 3 6/8
21/9 - 30/8 is -17/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 9 and 8 is 72
Next, find the equivalent fraction of both fractional numbers with denominator 72 - For the 1st fraction, since 9 × 8 = 72,
21/9 = 21 × 8/9 × 8 = 168/72 - Likewise, for the 2nd fraction, since 8 × 9 = 72,
30/8 = 30 × 9/8 × 9 = 270/72 - Subtract the two like fractions:
168/72 - 270/72 = 168 - 270/72 = -102/72 - After reducing the fraction, the answer is -17/12
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/9-30/8 21/9-60/8 21/18-30/8 21/9-30/16 63/9-30/8 21/9-90/8 21/27-30/8 21/9-30/24 21/45-30/8 21/9-30/40 21/63-30/8 21/9-30/56