Subtract 18/21 from 90/10
1st number: 9 0/10, 2nd number: 18/21
90/10 - 18/21 is 57/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 10 × 21 = 210,
90/10 = 90 × 21/10 × 21 = 1890/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
18/21 = 18 × 10/21 × 10 = 180/210 - Subtract the two like fractions:
1890/210 - 180/210 = 1890 - 180/210 = 1710/210 - After reducing the fraction, the answer is 57/7
- In mixed form: 81/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/10-36/21 90/20-18/21 90/10-18/42 90/10-54/21 90/30-18/21 90/10-18/63 90/10-90/21 90/50-18/21 90/70-18/21