Subtract 6/40 from 81/42
1st number: 1 39/42, 2nd number: 6/40
81/42 - 6/40 is 249/140.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 42 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 42 × 20 = 840,
81/42 = 81 × 20/42 × 20 = 1620/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
6/40 = 6 × 21/40 × 21 = 126/840 - Subtract the two like fractions:
1620/840 - 126/840 = 1620 - 126/840 = 1494/840 - After reducing the fraction, the answer is 249/140
- In mixed form: 1109/140
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 81/42-12/40 81/84-6/40 81/42-6/80 81/42-18/40 81/42-30/40 81/42-42/40