Subtract 20/42 from 90/30
1st number: 3 0/30, 2nd number: 20/42
90/30 - 20/42 is 53/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
90/30 = 90 × 7/30 × 7 = 630/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
20/42 = 20 × 5/42 × 5 = 100/210 - Subtract the two like fractions:
630/210 - 100/210 = 630 - 100/210 = 530/210 - After reducing the fraction, the answer is 53/21
- In mixed form: 211/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/30-40/42 90/60-20/42 90/30-20/84 90/30-60/42