Answers

Add 28/21 and 42/54

1^st number: 1 7/21, 2^nd number: 42/54

28/21 + 42/54 is 19/9.

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,
   28/21 = 28 × 18/21 × 18 = 504/378
3. Likewise, for the 2nd fraction, since 54 × 7 = 378,
   42/54 = 42 × 7/54 × 7 = 294/378
4. Add the two like fractions:
   504/378 + 294/378 = 504 + 294/378 = 798/378
5. 798/378 simplified gives 19/9
6. So, 28/21 + 42/54 = 19/9
   In mixed form: 21/9

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