Subtract 20/81 from 2/72
2/72 - 20/81 is -71/324.
Steps for subtracting fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 72 and 81 is 648
Next, find the equivalent fraction of both fractional numbers with denominator 648 - For the 1st fraction, since 72 × 9 = 648,
2/72 = 2 × 9/72 × 9 = 18/648 - Likewise, for the 2nd fraction, since 81 × 8 = 648,
20/81 = 20 × 8/81 × 8 = 160/648 - Subtract the two like fractions:
18/648 - 160/648 = 18 - 160/648 = -142/648 - After reducing the fraction, the answer is -71/324
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