Subtract 7/8 from 45/81
45/81 - 7/8 is -23/72.
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,
45/81 = 45 × 8/81 × 8 = 360/648 - Likewise, for the 2nd fraction, since 8 × 81 = 648,
7/8 = 7 × 81/8 × 81 = 567/648 - Subtract the two like fractions:
360/648 - 567/648 = 360 - 567/648 = -207/648 - After reducing the fraction, the answer is -23/72
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