Subtract 81/16 from 8/21
1st number: 8/21, 2nd number: 5 1/16
8/21 - 81/16 is -1573/336.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 16 is 336
Next, find the equivalent fraction of both fractional numbers with denominator 336 - For the 1st fraction, since 21 × 16 = 336,
8/21 = 8 × 16/21 × 16 = 128/336 - Likewise, for the 2nd fraction, since 16 × 21 = 336,
81/16 = 81 × 21/16 × 21 = 1701/336 - Subtract the two like fractions:
128/336 - 1701/336 = 128 - 1701/336 = -1573/336
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 16/21-81/16 8/42-81/16 8/21-81/32 24/21-81/16 8/63-81/16 8/21-81/48 40/21-81/16 8/21-81/80 56/21-81/16