Subtract 20/42 from 45/27
1st number: 1 18/27, 2nd number: 20/42
45/27 - 20/42 is 25/21.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 27 and 42 is 378
Next, find the equivalent fraction of both fractional numbers with denominator 378 - For the 1st fraction, since 27 × 14 = 378,
45/27 = 45 × 14/27 × 14 = 630/378 - Likewise, for the 2nd fraction, since 42 × 9 = 378,
20/42 = 20 × 9/42 × 9 = 180/378 - Subtract the two like fractions:
630/378 - 180/378 = 630 - 180/378 = 450/378 - After reducing the fraction, the answer is 25/21
- In mixed form: 14/21
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/27-20/42 45/27-40/42 45/54-20/42 45/27-20/84 45/27-60/42 45/81-20/42