Subtract 7/30 from 10/81
10/81 - 7/30 is -89/810.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 30 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 81 × 10 = 810,
10/81 = 10 × 10/81 × 10 = 100/810 - Likewise, for the 2nd fraction, since 30 × 27 = 810,
7/30 = 7 × 27/30 × 27 = 189/810 - Subtract the two like fractions:
100/810 - 189/810 = 100 - 189/810 = -89/810
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