Subtract 21/3 from 12/42
1st number: 12/42, 2nd number: 7 0/3
12/42 - 21/3 is -47/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 3 is 42
Next, find the equivalent fraction of both fractional numbers with denominator 42 - For the 1st fraction, since 42 × 1 = 42,
12/42 = 12 × 1/42 × 1 = 12/42 - Likewise, for the 2nd fraction, since 3 × 14 = 42,
21/3 = 21 × 14/3 × 14 = 294/42 - Subtract the two like fractions:
12/42 - 294/42 = 12 - 294/42 = -282/42 - After reducing the fraction, the answer is -47/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/42-21/3 12/42-42/3 12/84-21/3 12/42-21/6 36/42-21/3 12/42-63/3 12/42-21/9 60/42-21/3 12/42-21/15 84/42-21/3