Answers

Subtract 8/27 from 4/21

4/21 - 8/27 is -20/189.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 27 is 189
   
   Next, find the equivalent fraction of both fractional numbers with denominator 189
2. For the 1st fraction, since 21 × 9 = 189,
   4/21 = 4 × 9/21 × 9 = 36/189
3. Likewise, for the 2nd fraction, since 27 × 7 = 189,
   8/27 = 8 × 7/27 × 7 = 56/189
4. Subtract the two like fractions:
   36/189 - 56/189 = 36 - 56/189 = -20/189

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