Subtract 81/4 from 5/42
1st number: 5/42, 2nd number: 20 1/4
5/42 - 81/4 is -1691/84.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 4 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 42 × 2 = 84,
5/42 = 5 × 2/42 × 2 = 10/84 - Likewise, for the 2nd fraction, since 4 × 21 = 84,
81/4 = 81 × 21/4 × 21 = 1701/84 - Subtract the two like fractions:
10/84 - 1701/84 = 10 - 1701/84 = -1691/84
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 10/42-81/4 5/84-81/4 5/42-81/8 15/42-81/4 5/42-81/12 25/42-81/4 5/42-81/20 35/42-81/4 5/42-81/28