Subtract 20/45 from 45/42
1st number: 1 3/42, 2nd number: 20/45
45/42 - 20/45 is 79/126.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 45 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 42 × 15 = 630,
45/42 = 45 × 15/42 × 15 = 675/630 - Likewise, for the 2nd fraction, since 45 × 14 = 630,
20/45 = 20 × 14/45 × 14 = 280/630 - Subtract the two like fractions:
675/630 - 280/630 = 675 - 280/630 = 395/630 - After reducing the fraction, the answer is 79/126
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 90/42-20/45 45/42-40/45 45/84-20/45 45/42-20/90 45/42-60/45