Answers

Subtract 70/20 from 21/54

1^st number: 21/54, 2^nd number: 3 10/20

21/54 - 70/20 is -28/9.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 54 and 20 is 540
   
   Next, find the equivalent fraction of both fractional numbers with denominator 540
2. For the 1st fraction, since 54 × 10 = 540,
   21/54 = 21 × 10/54 × 10 = 210/540
3. Likewise, for the 2nd fraction, since 20 × 27 = 540,
   70/20 = 70 × 27/20 × 27 = 1890/540
4. Subtract the two like fractions:
   210/540 - 1890/540 = 210 - 1890/540 = -1680/540
5. After reducing the fraction, the answer is -28/9

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