Answers

Subtract 1/72 from 7/81

7/81 - 1/72 is 47/648.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 72 is 648
   
   Next, find the equivalent fraction of both fractional numbers with denominator 648
2. For the 1st fraction, since 81 × 8 = 648,
   7/81 = 7 × 8/81 × 8 = 56/648
3. Likewise, for the 2nd fraction, since 72 × 9 = 648,
   1/72 = 1 × 9/72 × 9 = 9/648
4. Subtract the two like fractions:
   56/648 - 9/648 = 56 - 9/648 = 47/648

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