Subtract 4/63 from 21/70
21/70 - 4/63 is 149/630.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 70 and 63 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 70 × 9 = 630,
21/70 = 21 × 9/70 × 9 = 189/630 - Likewise, for the 2nd fraction, since 63 × 10 = 630,
4/63 = 4 × 10/63 × 10 = 40/630 - Subtract the two like fractions:
189/630 - 40/630 = 189 - 40/630 = 149/630
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/70-4/63 21/70-8/63 63/70-4/63 21/70-12/63 21/70-20/63 21/70-28/63