Subtract 72/81 from 2/5
2/5 - 72/81 is -22/45.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 5 and 81 is 405
Next, find the equivalent fraction of both fractional numbers with denominator 405 - For the 1st fraction, since 5 × 81 = 405,
2/5 = 2 × 81/5 × 81 = 162/405 - Likewise, for the 2nd fraction, since 81 × 5 = 405,
72/81 = 72 × 5/81 × 5 = 360/405 - Subtract the two like fractions:
162/405 - 360/405 = 162 - 360/405 = -198/405 - After reducing the fraction, the answer is -22/45
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