Subtract 20/30 from 5/42
5/42 - 20/30 is -23/42.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 30 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
5/42 = 5 × 5/42 × 5 = 25/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
20/30 = 20 × 7/30 × 7 = 140/210 - Subtract the two like fractions:
25/210 - 140/210 = 25 - 140/210 = -115/210 - After reducing the fraction, the answer is -23/42
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 10/42-20/30 5/42-40/30 5/84-20/30 5/42-20/60 15/42-20/30 5/42-60/30 5/42-20/90 25/42-20/30 35/42-20/30