Answers

Add 21/28 and 84/81

1^st number: 21/28, 2^nd number: 1 3/81

21/28 + 84/81 is 193/108.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 28 and 81 is 2268
   
   Next, find the equivalent fraction of both fractional numbers with denominator 2268
2. For the 1st fraction, since 28 × 81 = 2268,
   21/28 = 21 × 81/28 × 81 = 1701/2268
3. Likewise, for the 2nd fraction, since 81 × 28 = 2268,
   84/81 = 84 × 28/81 × 28 = 2352/2268
4. Add the two like fractions:
   1701/2268 + 2352/2268 = 1701 + 2352/2268 = 4053/2268
5. 4053/2268 simplified gives 193/108
6. So, 21/28 + 84/81 = 193/108
   In mixed form: 185/108

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