Answers

Subtract 63/81 from 42/20

1^st number: 2 2/20, 2^nd number: 63/81

42/20 - 63/81 is 119/90.

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,
   42/20 = 42 × 81/20 × 81 = 3402/1620
3. Likewise, for the 2nd fraction, since 81 × 20 = 1620,
   63/81 = 63 × 20/81 × 20 = 1260/1620
4. Subtract the two like fractions:
   3402/1620 - 1260/1620 = 3402 - 1260/1620 = 2142/1620
5. After reducing the fraction, the answer is 119/90
6. In mixed form: 129/90

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