Subtract 1/42 from 20/45
20/45 - 1/42 is 53/126.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 42 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 45 × 14 = 630,
20/45 = 20 × 14/45 × 14 = 280/630 - Likewise, for the 2nd fraction, since 42 × 15 = 630,
1/42 = 1 × 15/42 × 15 = 15/630 - Subtract the two like fractions:
280/630 - 15/630 = 280 - 15/630 = 265/630 - After reducing the fraction, the answer is 53/126
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/45-1/42 20/45-2/42 20/90-1/42 20/45-1/84 60/45-1/42 20/45-3/42 20/45-5/42 20/45-7/42