Subtract 75/90 from 5/42
5/42 - 75/90 is -5/7.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 90 is 630
Next, find the equivalent fraction of both fractional numbers with denominator 630 - For the 1st fraction, since 42 × 15 = 630,
5/42 = 5 × 15/42 × 15 = 75/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
75/90 = 75 × 7/90 × 7 = 525/630 - Subtract the two like fractions:
75/630 - 525/630 = 75 - 525/630 = -450/630 - After reducing the fraction, the answer is -5/7
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 10/42-75/90 5/84-75/90 15/42-75/90 25/42-75/90 35/42-75/90