Subtract 63/18 from 81/84
1st number: 81/84, 2nd number: 3 9/18
81/84 - 63/18 is -71/28.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 18 is 252
Next, find the equivalent fraction of both fractional numbers with denominator 252 - For the 1st fraction, since 84 × 3 = 252,
81/84 = 81 × 3/84 × 3 = 243/252 - Likewise, for the 2nd fraction, since 18 × 14 = 252,
63/18 = 63 × 14/18 × 14 = 882/252 - Subtract the two like fractions:
243/252 - 882/252 = 243 - 882/252 = -639/252 - After reducing the fraction, the answer is -71/28
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 81/84-63/36 81/84-63/54 81/84-63/90