Subtract 63/12 from 81/90
1st number: 81/90, 2nd number: 5 3/12
81/90 - 63/12 is -87/20.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 90 and 12 is 180
Next, find the equivalent fraction of both fractional numbers with denominator 180 - For the 1st fraction, since 90 × 2 = 180,
81/90 = 81 × 2/90 × 2 = 162/180 - Likewise, for the 2nd fraction, since 12 × 15 = 180,
63/12 = 63 × 15/12 × 15 = 945/180 - Subtract the two like fractions:
162/180 - 945/180 = 162 - 945/180 = -783/180 - After reducing the fraction, the answer is -87/20
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 81/90-63/24 81/90-63/36 81/90-63/60 81/90-63/84