Subtract 20/45 from 1/42
1/42 - 20/45 is -53/126.
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,
1/42 = 1 × 15/42 × 15 = 15/630 - Likewise, for the 2nd fraction, since 45 × 14 = 630,
20/45 = 20 × 14/45 × 14 = 280/630 - Subtract the two like fractions:
15/630 - 280/630 = 15 - 280/630 = -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: 2/42-20/45 1/42-40/45 1/84-20/45 1/42-20/90 3/42-20/45 1/42-60/45 5/42-20/45 7/42-20/45