Subtract 72/20 from 70/80
1st number: 70/80, 2nd number: 3 12/20
70/80 - 72/20 is -109/40.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 80 and 20 is 80
Next, find the equivalent fraction of both fractional numbers with denominator 80 - For the 1st fraction, since 80 × 1 = 80,
70/80 = 70 × 1/80 × 1 = 70/80 - Likewise, for the 2nd fraction, since 20 × 4 = 80,
72/20 = 72 × 4/20 × 4 = 288/80 - Subtract the two like fractions:
70/80 - 288/80 = 70 - 288/80 = -218/80 - After reducing the fraction, the answer is -109/40
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 70/80-72/40 70/80-72/60