Subtract 35/40 from 20/81
20/81 - 35/40 is -407/648.
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,
20/81 = 20 × 40/81 × 40 = 800/3240 - Likewise, for the 2nd fraction, since 40 × 81 = 3240,
35/40 = 35 × 81/40 × 81 = 2835/3240 - Subtract the two like fractions:
800/3240 - 2835/3240 = 800 - 2835/3240 = -2035/3240 - After reducing the fraction, the answer is -407/648
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