Answers

Subtract 21/90 from 28/63

28/63 - 21/90 is 19/90.

Steps for subtracting fractions

1. 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
2. For the 1st fraction, since 63 × 10 = 630,
   28/63 = 28 × 10/63 × 10 = 280/630
3. Likewise, for the 2nd fraction, since 90 × 7 = 630,
   21/90 = 21 × 7/90 × 7 = 147/630
4. Subtract the two like fractions:
   280/630 - 147/630 = 280 - 147/630 = 133/630
5. After reducing the fraction, the answer is 19/90

MathStep (Works offline)

Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad

Related: ⁵⁶/₆₃-²¹/₉₀ ²⁸/₆₃-⁴²/₉₀ ⁸⁴/₆₃-²¹/₉₀ ²⁸/₆₃-⁶³/₉₀

Subtract Fractions Calculator