Subtract 9/40 from 7/81
7/81 - 9/40 is -449/3240.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 40 is 3240
Next, find the equivalent fraction of both fractional numbers with denominator 3240 - For the 1st fraction, since 81 × 40 = 3240,
7/81 = 7 × 40/81 × 40 = 280/3240 - Likewise, for the 2nd fraction, since 40 × 81 = 3240,
9/40 = 9 × 81/40 × 81 = 729/3240 - Subtract the two like fractions:
280/3240 - 729/3240 = 280 - 729/3240 = -449/3240
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