Answers

Subtract 18/4 from 7/81

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

7/81 - 18/4 is -715/162.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 4 is 324
   
   Next, find the equivalent fraction of both fractional numbers with denominator 324
2. For the 1st fraction, since 81 × 4 = 324,
   7/81 = 7 × 4/81 × 4 = 28/324
3. Likewise, for the 2nd fraction, since 4 × 81 = 324,
   18/4 = 18 × 81/4 × 81 = 1458/324
4. Subtract the two like fractions:
   28/324 - 1458/324 = 28 - 1458/324 = -1430/324
5. After reducing the fraction, the answer is -715/162

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