Answers

Subtract 21/50 from 4/81

4/81 - 21/50 is -1501/4050.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 50 is 4050
   
   Next, find the equivalent fraction of both fractional numbers with denominator 4050
2. For the 1st fraction, since 81 × 50 = 4050,
   4/81 = 4 × 50/81 × 50 = 200/4050
3. Likewise, for the 2nd fraction, since 50 × 81 = 4050,
   21/50 = 21 × 81/50 × 81 = 1701/4050
4. Subtract the two like fractions:
   200/4050 - 1701/4050 = 200 - 1701/4050 = -1501/4050

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