Subtract 18/90 from 10/42
10/42 - 18/90 is 4/105.
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,
10/42 = 10 × 15/42 × 15 = 150/630 - Likewise, for the 2nd fraction, since 90 × 7 = 630,
18/90 = 18 × 7/90 × 7 = 126/630 - Subtract the two like fractions:
150/630 - 126/630 = 150 - 126/630 = 24/630 - After reducing the fraction, the answer is 4/105
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 20/42-18/90 10/42-36/90 10/84-18/90 30/42-18/90 10/42-54/90 50/42-18/90 70/42-18/90