Subtract 70/21 from 12/4
1st number: 3 0/4, 2nd number: 3 7/21
12/4 - 70/21 is -1/3.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 4 and 21 is 84
Next, find the equivalent fraction of both fractional numbers with denominator 84 - For the 1st fraction, since 4 × 21 = 84,
12/4 = 12 × 21/4 × 21 = 252/84 - Likewise, for the 2nd fraction, since 21 × 4 = 84,
70/21 = 70 × 4/21 × 4 = 280/84 - Subtract the two like fractions:
252/84 - 280/84 = 252 - 280/84 = -28/84 - After reducing the fraction, the answer is -1/3
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 24/4-70/21 12/8-70/21 12/4-70/42 36/4-70/21 12/4-70/63 60/4-70/21 12/20-70/21 84/4-70/21 12/28-70/21