Answers

Subtract 42/81 from 21/7

1^st number: 3 0/7, 2^nd number: 42/81

21/7 - 42/81 is 67/27.

Steps for subtracting fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 7 and 81 is 567
   
   Next, find the equivalent fraction of both fractional numbers with denominator 567
2. For the 1st fraction, since 7 × 81 = 567,
   21/7 = 21 × 81/7 × 81 = 1701/567
3. Likewise, for the 2nd fraction, since 81 × 7 = 567,
   42/81 = 42 × 7/81 × 7 = 294/567
4. Subtract the two like fractions:
   1701/567 - 294/567 = 1701 - 294/567 = 1407/567
5. After reducing the fraction, the answer is 67/27
6. In mixed form: 213/27

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