Subtract 48/18 from 42/21
1st number: 2 0/21, 2nd number: 2 12/18
42/21 - 48/18 is -2/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 18 is 126
Next, find the equivalent fraction of both fractional numbers with denominator 126 - For the 1st fraction, since 21 × 6 = 126,
42/21 = 42 × 6/21 × 6 = 252/126 - Likewise, for the 2nd fraction, since 18 × 7 = 126,
48/18 = 48 × 7/18 × 7 = 336/126 - Subtract the two like fractions:
252/126 - 336/126 = 252 - 336/126 = -84/126 - After reducing the fraction, the answer is -2/3
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/21-48/18 42/21-96/18 42/21-48/36 42/63-48/18 42/21-48/54 42/21-48/90