Answers

Subtract 28/81 from 15/49

15/49 - 28/81 is -157/3969.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 49 and 81 is 3969
   
   Next, find the equivalent fraction of both fractional numbers with denominator 3969
2. For the 1st fraction, since 49 × 81 = 3969,
   15/49 = 15 × 81/49 × 81 = 1215/3969
3. Likewise, for the 2nd fraction, since 81 × 49 = 3969,
   28/81 = 28 × 49/81 × 49 = 1372/3969
4. Subtract the two like fractions:
   1215/3969 - 1372/3969 = 1215 - 1372/3969 = -157/3969

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