Answers

Subtract 15/81 from 49/20

1^st number: 2 9/20, 2^nd number: 15/81

49/20 - 15/81 is 1223/540.

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,
   49/20 = 49 × 81/20 × 81 = 3969/1620
3. Likewise, for the 2nd fraction, since 81 × 20 = 1620,
   15/81 = 15 × 20/81 × 20 = 300/1620
4. Subtract the two like fractions:
   3969/1620 - 300/1620 = 3969 - 300/1620 = 3669/1620
5. After reducing the fraction, the answer is 1223/540
6. In mixed form: 2143/540

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