Subtract 20/81 from 10/45
10/45 - 20/81 is -2/81.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 45 and 81 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 45 × 9 = 405,
10/45 = 10 × 9/45 × 9 = 90/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
20/81 = 20 × 5/81 × 5 = 100/405 - Subtract the two like fractions:
90/405 - 100/405 = 90 - 100/405 = -10/405 - After reducing the fraction, the answer is -2/81
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