Subtract 40/81 from 9/30
9/30 - 40/81 is -157/810.
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,
9/30 = 9 × 27/30 × 27 = 243/810 - Likewise, for the 2nd fraction, since 81 × 10 = 810,
40/81 = 40 × 10/81 × 10 = 400/810 - Subtract the two like fractions:
243/810 - 400/810 = 243 - 400/810 = -157/810
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