Subtract 42/70 from 72/84
72/84 - 42/70 is 9/35.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 70 is 420
Next, find the equivalent fraction of both fractional numbers with denominator 420 - For the 1st fraction, since 84 × 5 = 420,
72/84 = 72 × 5/84 × 5 = 360/420 - Likewise, for the 2nd fraction, since 70 × 6 = 420,
42/70 = 42 × 6/70 × 6 = 252/420 - Subtract the two like fractions:
360/420 - 252/420 = 360 - 252/420 = 108/420 - After reducing the fraction, the answer is 9/35
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 72/84-84/70