Subtract 30/42 from 3/10
3/10 - 30/42 is -29/70.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 10 and 42 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 10 × 21 = 210,
3/10 = 3 × 21/10 × 21 = 63/210 - Likewise, for the 2nd fraction, since 42 × 5 = 210,
30/42 = 30 × 5/42 × 5 = 150/210 - Subtract the two like fractions:
63/210 - 150/210 = 63 - 150/210 = -87/210 - After reducing the fraction, the answer is -29/70
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 6/10-30/42 3/10-60/42 3/20-30/42 3/10-30/84 9/10-30/42 3/10-90/42 3/30-30/42 15/10-30/42 3/50-30/42 21/10-30/42 3/70-30/42