Answers

Subtract 21/16 from 45/81

1^st number: 45/81, 2^nd number: 1 5/16

45/81 - 21/16 is -109/144.

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,
   45/81 = 45 × 16/81 × 16 = 720/1296
3. Likewise, for the 2nd fraction, since 16 × 81 = 1296,
   21/16 = 21 × 81/16 × 81 = 1701/1296
4. Subtract the two like fractions:
   720/1296 - 1701/1296 = 720 - 1701/1296 = -981/1296
5. After reducing the fraction, the answer is -109/144

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