Subtract 81/15 from 25/42
1st number: 25/42, 2nd number: 5 6/15
25/42 - 81/15 is -1009/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 15 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
25/42 = 25 × 5/42 × 5 = 125/210 - Likewise, for the 2nd fraction, since 15 × 14 = 210,
81/15 = 81 × 14/15 × 14 = 1134/210 - Subtract the two like fractions:
125/210 - 1134/210 = 125 - 1134/210 = -1009/210
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 50/42-81/15 25/84-81/15 25/42-81/30 75/42-81/15 25/42-81/45 25/42-81/75