Subtract 5/21 from 18/70
18/70 - 5/21 is 2/105.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 21 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 70 × 3 = 210,
18/70 = 18 × 3/70 × 3 = 54/210 - Likewise, for the 2nd fraction, since 21 × 10 = 210,
5/21 = 5 × 10/21 × 10 = 50/210 - Subtract the two like fractions:
54/210 - 50/210 = 54 - 50/210 = 4/210 - After reducing the fraction, the answer is 2/105
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 36/70-5/21 18/70-10/21 18/70-5/42 54/70-5/21 18/70-15/21 18/70-5/63 90/70-5/21 18/70-25/21 18/70-35/21