Subtract 54/21 from 63/42
1st number: 1 21/42, 2nd number: 2 12/21
63/42 - 54/21 is -15/14.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 21 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
63/42 = 63 × 1/42 × 1 = 63/42 - Likewise, for the 2nd fraction, since 21 × 2 = 42,
54/21 = 54 × 2/21 × 2 = 108/42 - Subtract the two like fractions:
63/42 - 108/42 = 63 - 108/42 = -45/42 - After reducing the fraction, the answer is -15/14
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 63/84-54/21 63/42-54/42 63/42-54/63