Subtract 42/90 from 8/42
8/42 - 42/90 is -29/105.
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,
8/42 = 8 × 15/42 × 15 = 120/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
42/90 = 42 × 7/90 × 7 = 294/630 - Subtract the two like fractions:
120/630 - 294/630 = 120 - 294/630 = -174/630 - After reducing the fraction, the answer is -29/105
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 16/42-42/90 8/42-84/90 8/84-42/90 24/42-42/90 40/42-42/90 56/42-42/90