Answers

Add 7/21 and 81/28

1^st number: 7/21, 2^nd number: 2 25/28

7/21 + 81/28 is 271/84.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 28 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 21 × 4 = 84,
   7/21 = 7 × 4/21 × 4 = 28/84
3. Likewise, for the 2nd fraction, since 28 × 3 = 84,
   81/28 = 81 × 3/28 × 3 = 243/84
4. Add the two like fractions:
   28/84 + 243/84 = 28 + 243/84 = 271/84
5. So, 7/21 + 81/28 = 271/84
   In mixed form: 319/84

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