Subtract 18/40 from 50/21
1st number: 2 8/21, 2nd number: 18/40
50/21 - 18/40 is 811/420.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
50/21 = 50 × 40/21 × 40 = 2000/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
18/40 = 18 × 21/40 × 21 = 378/840 - Subtract the two like fractions:
2000/840 - 378/840 = 2000 - 378/840 = 1622/840 - After reducing the fraction, the answer is 811/420
- In mixed form: 1391/420
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 50/21-36/40 50/42-18/40 50/21-18/80 50/21-54/40 50/63-18/40 50/21-90/40