Subtract 90/21 from 30/5
1st number: 6 0/5, 2nd number: 4 6/21
30/5 - 90/21 is 12/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 21 is 105
Next, find the equivalent fraction of both fractional numbers with denominator 105 - For the 1st fraction, since 5 × 21 = 105,
30/5 = 30 × 21/5 × 21 = 630/105 - Likewise, for the 2nd fraction, since 21 × 5 = 105,
90/21 = 90 × 5/21 × 5 = 450/105 - Subtract the two like fractions:
630/105 - 450/105 = 630 - 450/105 = 180/105 - After reducing the fraction, the answer is 12/7
- In mixed form: 15/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 60/5-90/21 30/10-90/21 30/5-90/42 90/5-90/21 30/15-90/21 30/5-90/63 30/25-90/21 30/35-90/21