Subtract 21/35 from 1/42
1/42 - 21/35 is -121/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 35 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
1/42 = 1 × 5/42 × 5 = 5/210 - Likewise, for the 2nd fraction, since 35 × 6 = 210,
21/35 = 21 × 6/35 × 6 = 126/210 - Subtract the two like fractions:
5/210 - 126/210 = 5 - 126/210 = -121/210
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 2/42-21/35 1/42-42/35 1/84-21/35 1/42-21/70 3/42-21/35 1/42-63/35 5/42-21/35 7/42-21/35