Answers

Subtract 21/81 from 2/7

2/7 - 21/81 is 5/189.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 7 and 81 is 567
   
   Next, find the equivalent fraction of both fractional numbers with denominator 567
2. For the 1st fraction, since 7 × 81 = 567,
   2/7 = 2 × 81/7 × 81 = 162/567
3. Likewise, for the 2nd fraction, since 81 × 7 = 567,
   21/81 = 21 × 7/81 × 7 = 147/567
4. Subtract the two like fractions:
   162/567 - 147/567 = 162 - 147/567 = 15/567
5. After reducing the fraction, the answer is 5/189

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