Answers

Subtract 49/9 from 81/21

1^st number: 3 18/21, 2^nd number: 5 4/9

81/21 - 49/9 is -100/63.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 9 is 63
   
   Next, find the equivalent fraction of both fractional numbers with denominator 63
2. For the 1st fraction, since 21 × 3 = 63,
   81/21 = 81 × 3/21 × 3 = 243/63
3. Likewise, for the 2nd fraction, since 9 × 7 = 63,
   49/9 = 49 × 7/9 × 7 = 343/63
4. Subtract the two like fractions:
   243/63 - 343/63 = 243 - 343/63 = -100/63

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