Subtract 18/21 from 42/27
1st number: 1 15/27, 2nd number: 18/21
42/27 - 18/21 is 44/63.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 21 is 189
Next, find the equivalent fraction of both fractional numbers with denominator 189 - For the 1st fraction, since 27 × 7 = 189,
42/27 = 42 × 7/27 × 7 = 294/189 - Likewise, for the 2nd fraction, since 21 × 9 = 189,
18/21 = 18 × 9/21 × 9 = 162/189 - Subtract the two like fractions:
294/189 - 162/189 = 294 - 162/189 = 132/189 - After reducing the fraction, the answer is 44/63
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/27-18/21 42/27-36/21 42/54-18/21 42/27-18/42 42/27-54/21 42/81-18/21 42/27-18/63 42/27-90/21