Subtract 42/4 from 1/21
1st number: 1/21, 2nd number: 10 2/4
1/21 - 42/4 is -439/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 4 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 21 × 4 = 84,
1/21 = 1 × 4/21 × 4 = 4/84 - Likewise, for the 2nd fraction, since 4 × 21 = 84,
42/4 = 42 × 21/4 × 21 = 882/84 - Subtract the two like fractions:
4/84 - 882/84 = 4 - 882/84 = -878/84 - After reducing the fraction, the answer is -439/42
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 2/21-42/4 1/21-84/4 1/42-42/4 1/21-42/8 3/21-42/4 1/63-42/4 1/21-42/12 5/21-42/4 1/21-42/20 7/21-42/4 1/21-42/28