Subtract 50/90 from 40/42
40/42 - 50/90 is 25/63.
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,
40/42 = 40 × 15/42 × 15 = 600/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
50/90 = 50 × 7/90 × 7 = 350/630 - Subtract the two like fractions:
600/630 - 350/630 = 600 - 350/630 = 250/630 - After reducing the fraction, the answer is 25/63
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 80/42-50/90 40/84-50/90