Subtract 21/81 from 4/16
4/16 - 21/81 is -1/108.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 16 and 81 is 1296
Next, find the equivalent fraction of both fractional numbers with denominator 1296 - For the 1st fraction, since 16 × 81 = 1296,
4/16 = 4 × 81/16 × 81 = 324/1296 - Likewise, for the 2nd fraction, since 81 × 16 = 1296,
21/81 = 21 × 16/81 × 16 = 336/1296 - Subtract the two like fractions:
324/1296 - 336/1296 = 324 - 336/1296 = -12/1296 - After reducing the fraction, the answer is -1/108
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