Subtract 30/81 from 7/30
7/30 - 30/81 is -37/270.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 30 and 81 is 810
Next, find the equivalent fraction of both fractional numbers with denominator 810 - For the 1st fraction, since 30 × 27 = 810,
7/30 = 7 × 27/30 × 27 = 189/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
30/81 = 30 × 10/81 × 10 = 300/810 - Subtract the two like fractions:
189/810 - 300/810 = 189 - 300/810 = -111/810 - After reducing the fraction, the answer is -37/270
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