Subtract 21/16 from 7/81
1st number: 7/81, 2nd number: 1 5/16
7/81 - 21/16 is -1589/1296.
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,
7/81 = 7 × 16/81 × 16 = 112/1296 - Likewise, for the 2nd fraction, since 16 × 81 = 1296,
21/16 = 21 × 81/16 × 81 = 1701/1296 - Subtract the two like fractions:
112/1296 - 1701/1296 = 112 - 1701/1296 = -1589/1296
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