Subtract 63/7 from 42/21
1st number: 2 0/21, 2nd number: 9 0/7
42/21 - 63/7 is -7/1.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 7 is 21
Next, find the equivalent fraction of both fractional numbers with denominator 21 - For the 1st fraction, since 21 × 1 = 21,
42/21 = 42 × 1/21 × 1 = 42/21 - Likewise, for the 2nd fraction, since 7 × 3 = 21,
63/7 = 63 × 3/7 × 3 = 189/21 - Subtract the two like fractions:
42/21 - 189/21 = 42 - 189/21 = -147/21 - After reducing the fraction, the answer is -7/1
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 84/21-63/7 42/21-63/14 42/63-63/7 42/21-63/21 42/21-63/35 42/21-63/49