Subtract 21/8 from 1/81
1st number: 1/81, 2nd number: 2 5/8
1/81 - 21/8 is -1693/648.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 8 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 81 × 8 = 648,
1/81 = 1 × 8/81 × 8 = 8/648 - Likewise, for the 2nd fraction, since 8 × 81 = 648,
21/8 = 21 × 81/8 × 81 = 1701/648 - Subtract the two like fractions:
8/648 - 1701/648 = 8 - 1701/648 = -1693/648
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