Subtract 21/90 from 1/63
1/63 - 21/90 is -137/630.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 63 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 63 × 10 = 630,
1/63 = 1 × 10/63 × 10 = 10/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
21/90 = 21 × 7/90 × 7 = 147/630 - Subtract the two like fractions:
10/630 - 147/630 = 10 - 147/630 = -137/630
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 2/63-21/90 1/63-42/90 3/63-21/90 1/63-63/90 5/63-21/90 7/63-21/90