Subtract 20/81 from 5/40
5/40 - 20/81 is -79/648.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 40 and 81 is 3240
Next, find the equivalent fraction of both fractional numbers with denominator 3240 - For the 1st fraction, since 40 × 81 = 3240,
5/40 = 5 × 81/40 × 81 = 405/3240 - Likewise, for the 2nd fraction, since 81 × 40 = 3240,
20/81 = 20 × 40/81 × 40 = 800/3240 - Subtract the two like fractions:
405/3240 - 800/3240 = 405 - 800/3240 = -395/3240 - After reducing the fraction, the answer is -79/648
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