Subtract 20/54 from 25/42
25/42 - 20/54 is 85/378.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 54 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 42 × 9 = 378,
25/42 = 25 × 9/42 × 9 = 225/378 - Likewise, for the 2nd fraction, since 54 × 7 = 378,
20/54 = 20 × 7/54 × 7 = 140/378 - Subtract the two like fractions:
225/378 - 140/378 = 225 - 140/378 = 85/378
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 50/42-20/54 25/42-40/54 25/84-20/54 75/42-20/54 25/42-60/54