Subtract 7/15 from 5/81
5/81 - 7/15 is -164/405.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 81 and 15 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 81 × 5 = 405,
5/81 = 5 × 5/81 × 5 = 25/405 - Likewise, for the 2nd fraction, since 15 × 27 = 405,
7/15 = 7 × 27/15 × 27 = 189/405 - Subtract the two like fractions:
25/405 - 189/405 = 25 - 189/405 = -164/405
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