Subtract 50/45 from 20/42
1st number: 20/42, 2nd number: 1 5/45
20/42 - 50/45 is -40/63.
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,
20/42 = 20 × 15/42 × 15 = 300/630 - Likewise, for the 2nd fraction, since 45 × 14 = 630,
50/45 = 50 × 14/45 × 14 = 700/630 - Subtract the two like fractions:
300/630 - 700/630 = 300 - 700/630 = -400/630 - After reducing the fraction, the answer is -40/63
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 40/42-50/45 20/84-50/45 20/42-50/90 60/42-50/45