Answers

Subtract 70/20 from 50/81

1^st number: 50/81, 2^nd number: 3 10/20

50/81 - 70/20 is -467/162.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 81 and 20 is 1620
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1620
2. For the 1st fraction, since 81 × 20 = 1620,
   50/81 = 50 × 20/81 × 20 = 1000/1620
3. Likewise, for the 2nd fraction, since 20 × 81 = 1620,
   70/20 = 70 × 81/20 × 81 = 5670/1620
4. Subtract the two like fractions:
   1000/1620 - 5670/1620 = 1000 - 5670/1620 = -4670/1620
5. After reducing the fraction, the answer is -467/162

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