Answers

Subtract 42/81 from 2/21

2/21 - 42/81 is -80/189.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 81 is 567
   
   Next, find the equivalent fraction of both fractional numbers with denominator 567
2. For the 1st fraction, since 21 × 27 = 567,
   2/21 = 2 × 27/21 × 27 = 54/567
3. Likewise, for the 2nd fraction, since 81 × 7 = 567,
   42/81 = 42 × 7/81 × 7 = 294/567
4. Subtract the two like fractions:
   54/567 - 294/567 = 54 - 294/567 = -240/567
5. After reducing the fraction, the answer is -80/189

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