Subtract 15/40 from 54/21
1st number: 2 12/21, 2nd number: 15/40
54/21 - 15/40 is 123/56.
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,
54/21 = 54 × 40/21 × 40 = 2160/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
15/40 = 15 × 21/40 × 21 = 315/840 - Subtract the two like fractions:
2160/840 - 315/840 = 2160 - 315/840 = 1845/840 - After reducing the fraction, the answer is 123/56
- In mixed form: 211/56
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 54/21-30/40 54/42-15/40 54/21-15/80 54/21-45/40 54/63-15/40 54/21-75/40