Subtract 9/10 from 7/81
7/81 - 9/10 is -659/810.
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,
9/10 = 9 × 81/10 × 81 = 729/810 - Subtract the two like fractions:
70/810 - 729/810 = 70 - 729/810 = -659/810
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