Subtract 9/10 from 10/42
10/42 - 9/10 is -139/210.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 10 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
10/42 = 10 × 5/42 × 5 = 50/210 - Likewise, for the 2nd fraction, since 10 × 21 = 210,
9/10 = 9 × 21/10 × 21 = 189/210 - Subtract the two like fractions:
50/210 - 189/210 = 50 - 189/210 = -139/210
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 20/42-9/10 10/42-18/10 10/84-9/10 10/42-9/20 30/42-9/10 10/42-27/10 10/42-9/30 50/42-9/10 10/42-45/10 10/42-9/50 70/42-9/10 10/42-63/10 10/42-9/70