Subtract 4/12 from 90/70
1st number: 1 20/70, 2nd number: 4/12
90/70 - 4/12 is 20/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 12 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 70 × 6 = 420,
90/70 = 90 × 6/70 × 6 = 540/420 - Likewise, for the 2nd fraction, since 12 × 35 = 420,
4/12 = 4 × 35/12 × 35 = 140/420 - Subtract the two like fractions:
540/420 - 140/420 = 540 - 140/420 = 400/420 - After reducing the fraction, the answer is 20/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/70-8/12 90/70-4/24 90/70-4/36 90/70-20/12 90/70-4/60 90/70-28/12 90/70-4/84