Subtract 15/18 from 30/84
30/84 - 15/18 is -10/21.
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,
30/84 = 30 × 3/84 × 3 = 90/252 - Likewise, for the 2nd fraction, since 18 × 14 = 252,
15/18 = 15 × 14/18 × 14 = 210/252 - Subtract the two like fractions:
90/252 - 210/252 = 90 - 210/252 = -120/252 - After reducing the fraction, the answer is -10/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 60/84-15/18 30/84-30/18 30/84-15/36 90/84-15/18 30/84-45/18 30/84-15/54 30/84-75/18 30/84-15/90