Subtract 18/10 from 72/42
1st number: 1 30/42, 2nd number: 1 8/10
72/42 - 18/10 is -3/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 10 is 210
Next, find the equivalent fraction of both fractional numbers with denominator 210 - For the 1st fraction, since 42 × 5 = 210,
72/42 = 72 × 5/42 × 5 = 360/210 - Likewise, for the 2nd fraction, since 10 × 21 = 210,
18/10 = 18 × 21/10 × 21 = 378/210 - Subtract the two like fractions:
360/210 - 378/210 = 360 - 378/210 = -18/210 - 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: 72/42-36/10 72/84-18/10 72/42-18/20 72/42-54/10 72/42-18/30 72/42-90/10 72/42-18/50 72/42-18/70