Subtract 20/81 from 12/45
12/45 - 20/81 is 8/405.
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,
12/45 = 12 × 9/45 × 9 = 108/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
20/81 = 20 × 5/81 × 5 = 100/405 - Subtract the two like fractions:
108/405 - 100/405 = 108 - 100/405 = 8/405
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