Subtract 16/20 from 30/42
30/42 - 16/20 is -3/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 20 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 42 × 10 = 420,
30/42 = 30 × 10/42 × 10 = 300/420 - Likewise, for the 2nd fraction, since 20 × 21 = 420,
16/20 = 16 × 21/20 × 21 = 336/420 - Subtract the two like fractions:
300/420 - 336/420 = 300 - 336/420 = -36/420 - After reducing the fraction, the answer is -3/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 60/42-16/20 30/42-32/20 30/84-16/20 30/42-16/40 90/42-16/20 30/42-48/20 30/42-16/60 30/42-80/20