Subtract 8/10 from 7/81
7/81 - 8/10 is -289/405.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 10 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 81 × 10 = 810,
7/81 = 7 × 10/81 × 10 = 70/810 - Likewise, for the 2nd fraction, since 10 × 81 = 810,
8/10 = 8 × 81/10 × 81 = 648/810 - Subtract the two like fractions:
70/810 - 648/810 = 70 - 648/810 = -578/810 - After reducing the fraction, the answer is -289/405
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