Answers

Subtract 20/5 from 7/81

1^st number: 7/81, 2^nd number: 4 0/5

7/81 - 20/5 is -317/81.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 5 is 405
   
   Next, find the equivalent fraction of both fractional numbers with denominator 405
2. For the 1st fraction, since 81 × 5 = 405,
   7/81 = 7 × 5/81 × 5 = 35/405
3. Likewise, for the 2nd fraction, since 5 × 81 = 405,
   20/5 = 20 × 81/5 × 81 = 1620/405
4. Subtract the two like fractions:
   35/405 - 1620/405 = 35 - 1620/405 = -1585/405
5. After reducing the fraction, the answer is -317/81

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