Answers

Subtract 80/21 from 20/27

1^st number: 20/27, 2^nd number: 3 17/21

20/27 - 80/21 is -580/189.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 27 and 21 is 189
   
   Next, find the equivalent fraction of both fractional numbers with denominator 189
2. For the 1st fraction, since 27 × 7 = 189,
   20/27 = 20 × 7/27 × 7 = 140/189
3. Likewise, for the 2nd fraction, since 21 × 9 = 189,
   80/21 = 80 × 9/21 × 9 = 720/189
4. Subtract the two like fractions:
   140/189 - 720/189 = 140 - 720/189 = -580/189

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