Answers

Subtract 49/16 from 21/81

1^st number: 21/81, 2^nd number: 3 1/16

21/81 - 49/16 is -1211/432.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 16 is 1296
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1296
2. For the 1st fraction, since 81 × 16 = 1296,
   21/81 = 21 × 16/81 × 16 = 336/1296
3. Likewise, for the 2nd fraction, since 16 × 81 = 1296,
   49/16 = 49 × 81/16 × 81 = 3969/1296
4. Subtract the two like fractions:
   336/1296 - 3969/1296 = 336 - 3969/1296 = -3633/1296
5. After reducing the fraction, the answer is -1211/432

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