Subtract 30/40 from 70/84
70/84 - 30/40 is 1/12.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 84 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 84 × 10 = 840,
70/84 = 70 × 10/84 × 10 = 700/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
30/40 = 30 × 21/40 × 21 = 630/840 - Subtract the two like fractions:
700/840 - 630/840 = 700 - 630/840 = 70/840 - After reducing the fraction, the answer is 1/12
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 70/84-60/40 70/84-30/80 70/84-90/40