Subtract 42/27 from 21/8
1st number: 2 5/8, 2nd number: 1 15/27
21/8 - 42/27 is 77/72.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 27 is 216
Next, find the equivalent fraction of both fractional numbers with denominator 216 - For the 1st fraction, since 8 × 27 = 216,
21/8 = 21 × 27/8 × 27 = 567/216 - Likewise, for the 2nd fraction, since 27 × 8 = 216,
42/27 = 42 × 8/27 × 8 = 336/216 - Subtract the two like fractions:
567/216 - 336/216 = 567 - 336/216 = 231/216 - After reducing the fraction, the answer is 77/72
- In mixed form: 15/72
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/8-42/27 21/8-84/27 21/16-42/27 21/8-42/54 63/8-42/27 21/24-42/27 21/8-42/81 21/40-42/27 21/56-42/27