Subtract 70/21 from 1/40
1st number: 1/40, 2nd number: 3 7/21
1/40 - 70/21 is -397/120.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 21 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 40 × 21 = 840,
1/40 = 1 × 21/40 × 21 = 21/840 - Likewise, for the 2nd fraction, since 21 × 40 = 840,
70/21 = 70 × 40/21 × 40 = 2800/840 - Subtract the two like fractions:
21/840 - 2800/840 = 21 - 2800/840 = -2779/840 - After reducing the fraction, the answer is -397/120
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 2/40-70/21 1/80-70/21 1/40-70/42 3/40-70/21 1/40-70/63 5/40-70/21 7/40-70/21