Answers

Add 12/21 and 84/54

1^st number: 12/21, 2^nd number: 1 30/54

12/21 + 84/54 is 134/63.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 54 is 378
   
   Next, find the equivalent fraction of both fractional numbers with denominator 378
2. For the 1st fraction, since 21 × 18 = 378,
   12/21 = 12 × 18/21 × 18 = 216/378
3. Likewise, for the 2nd fraction, since 54 × 7 = 378,
   84/54 = 84 × 7/54 × 7 = 588/378
4. Add the two like fractions:
   216/378 + 588/378 = 216 + 588/378 = 804/378
5. 804/378 simplified gives 134/63
6. So, 12/21 + 84/54 = 134/63
   In mixed form: 28/63

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