Subtract 20/45 from 4/81
4/81 - 20/45 is -32/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 45 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 81 × 5 = 405,
4/81 = 4 × 5/81 × 5 = 20/405 - Likewise, for the 2nd fraction, since 45 × 9 = 405,
20/45 = 20 × 9/45 × 9 = 180/405 - Subtract the two like fractions:
20/405 - 180/405 = 20 - 180/405 = -160/405 - After reducing the fraction, the answer is -32/81
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