Subtract 3/16 from 21/81
21/81 - 3/16 is 31/432.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 16 is 1296
Next, find the equivalent fraction of both fractional numbers with denominator 1296 - For the 1st fraction, since 81 × 16 = 1296,
21/81 = 21 × 16/81 × 16 = 336/1296 - Likewise, for the 2nd fraction, since 16 × 81 = 1296,
3/16 = 3 × 81/16 × 81 = 243/1296 - Subtract the two like fractions:
336/1296 - 243/1296 = 336 - 243/1296 = 93/1296 - After reducing the fraction, the answer is 31/432
MathStep (Works offline)
Download our mobile app and learn to work with fractions in your own time:
Android and iPhone/ iPad
Related: 42/81-3/16 21/81-6/16 21/81-3/32 63/81-3/16 21/81-9/16 21/81-3/48 21/81-15/16 21/81-3/80 21/81-21/16