Answers

Subtract 42/81 from 84/20

1^st number: 4 4/20, 2^nd number: 42/81

84/20 - 42/81 is 497/135.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 81 is 1620
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1620
2. For the 1st fraction, since 20 × 81 = 1620,
   84/20 = 84 × 81/20 × 81 = 6804/1620
3. Likewise, for the 2nd fraction, since 81 × 20 = 1620,
   42/81 = 42 × 20/81 × 20 = 840/1620
4. Subtract the two like fractions:
   6804/1620 - 840/1620 = 6804 - 840/1620 = 5964/1620
5. After reducing the fraction, the answer is 497/135
6. In mixed form: 392/135

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