Subtract 12/42 from 3/30
3/30 - 12/42 is -13/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 30 × 7 = 210,
3/30 = 3 × 7/30 × 7 = 21/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
12/42 = 12 × 5/42 × 5 = 60/210 - Subtract the two like fractions:
21/210 - 60/210 = 21 - 60/210 = -39/210 - After reducing the fraction, the answer is -13/70
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 6/30-12/42 3/30-24/42 3/60-12/42 3/30-12/84 9/30-12/42 3/30-36/42 3/90-12/42 15/30-12/42 3/30-60/42 21/30-12/42 3/30-84/42