Subtract 3/42 from 21/35
21/35 - 3/42 is 37/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 35 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 35 × 6 = 210,
21/35 = 21 × 6/35 × 6 = 126/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
3/42 = 3 × 5/42 × 5 = 15/210 - Subtract the two like fractions:
126/210 - 15/210 = 126 - 15/210 = 111/210 - After reducing the fraction, the answer is 37/70
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/35-3/42 21/35-6/42 21/70-3/42 21/35-3/84 63/35-3/42 21/35-9/42 21/35-15/42 21/35-21/42