Subtract 21/81 from 1/8
1/8 - 21/81 is -29/216.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 8 and 81 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 8 × 81 = 648,
1/8 = 1 × 81/8 × 81 = 81/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
21/81 = 21 × 8/81 × 8 = 168/648 - Subtract the two like fractions:
81/648 - 168/648 = 81 - 168/648 = -87/648 - After reducing the fraction, the answer is -29/216
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