Subtract 42/63 from 28/21
1st number: 1 7/21, 2nd number: 42/63
28/21 - 42/63 is 2/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 63 is 63
Next, find the equivalent fraction of both fractional numbers with denominator 63 - For the 1st fraction, since 21 × 3 = 63,
28/21 = 28 × 3/21 × 3 = 84/63 - Likewise, for the 2nd fraction, since 63 × 1 = 63,
42/63 = 42 × 1/63 × 1 = 42/63 - Subtract the two like fractions:
84/63 - 42/63 = 84 - 42/63 = 42/63 - 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: 56/21-42/63 28/21-84/63 28/42-42/63 84/21-42/63 28/63-42/63