Answers

Add 21/84 and 70/81

21/84 + 70/81 is 361/324.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 81 is 2268
   
   Next, find the equivalent fraction of both fractional numbers with denominator 2268
2. For the 1st fraction, since 84 × 27 = 2268,
   21/84 = 21 × 27/84 × 27 = 567/2268
3. Likewise, for the 2nd fraction, since 81 × 28 = 2268,
   70/81 = 70 × 28/81 × 28 = 1960/2268
4. Add the two like fractions:
   567/2268 + 1960/2268 = 567 + 1960/2268 = 2527/2268
5. 2527/2268 simplified gives 361/324
6. So, 21/84 + 70/81 = 361/324
   In mixed form: 137/324

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