Answers

Subtract 64/9 from 21/84

1^st number: 21/84, 2^nd number: 7 1/9

21/84 - 64/9 is -247/36.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 9 is 252
   
   Next, find the equivalent fraction of both fractional numbers with denominator 252
2. For the 1st fraction, since 84 × 3 = 252,
   21/84 = 21 × 3/84 × 3 = 63/252
3. Likewise, for the 2nd fraction, since 9 × 28 = 252,
   64/9 = 64 × 28/9 × 28 = 1792/252
4. Subtract the two like fractions:
   63/252 - 1792/252 = 63 - 1792/252 = -1729/252
5. After reducing the fraction, the answer is -247/36

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