Subtract 20/16 from 21/81
1st number: 21/81, 2nd number: 1 4/16
21/81 - 20/16 is -107/108.
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,
20/16 = 20 × 81/16 × 81 = 1620/1296 - Subtract the two like fractions:
336/1296 - 1620/1296 = 336 - 1620/1296 = -1284/1296 - After reducing the fraction, the answer is -107/108
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