Subtract 16/45 from 3/21
3/21 - 16/45 is -67/315.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 45 is 315
Next, find the equivalent fraction of both fractional numbers with denominator 315 - For the 1st fraction, since 21 × 15 = 315,
3/21 = 3 × 15/21 × 15 = 45/315 - Likewise, for the 2nd fraction, since 45 × 7 = 315,
16/45 = 16 × 7/45 × 7 = 112/315 - Subtract the two like fractions:
45/315 - 112/315 = 45 - 112/315 = -67/315
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 6/21-16/45 3/21-32/45 3/42-16/45 3/21-16/90 9/21-16/45 3/21-48/45 3/63-16/45 15/21-16/45 3/21-80/45