Subtract 28/30 from 30/42
30/42 - 28/30 is -23/105.
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,
30/42 = 30 × 5/42 × 5 = 150/210 - Likewise, for the 2nd fraction, since 30 × 7 = 210,
28/30 = 28 × 7/30 × 7 = 196/210 - Subtract the two like fractions:
150/210 - 196/210 = 150 - 196/210 = -46/210 - After reducing the fraction, the answer is -23/105
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 60/42-28/30 30/42-56/30 30/84-28/30 30/42-28/60 90/42-28/30 30/42-84/30 30/42-28/90