Subtract 63/21 from 90/8
1st number: 11 2/8, 2nd number: 3 0/21
90/8 - 63/21 is 33/4.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 21 is 168
Next, find the equivalent fraction of both fractional numbers with denominator 168 - For the 1st fraction, since 8 × 21 = 168,
90/8 = 90 × 21/8 × 21 = 1890/168 - Likewise, for the 2nd fraction, since 21 × 8 = 168,
63/21 = 63 × 8/21 × 8 = 504/168 - Subtract the two like fractions:
1890/168 - 504/168 = 1890 - 504/168 = 1386/168 - After reducing the fraction, the answer is 33/4
- In mixed form: 81/4
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/16-63/21 90/8-63/42 90/24-63/21 90/40-63/21 90/56-63/21