Answers

Add 42/21 and 45/54

1^st number: 2 0/21, 2^nd number: 45/54

42/21 + 45/54 is 17/6.

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,
   42/21 = 42 × 18/21 × 18 = 756/378
3. Likewise, for the 2nd fraction, since 54 × 7 = 378,
   45/54 = 45 × 7/54 × 7 = 315/378
4. Add the two like fractions:
   756/378 + 315/378 = 756 + 315/378 = 1071/378
5. 1071/378 simplified gives 17/6
6. So, 42/21 + 45/54 = 17/6
   In mixed form: 25/6

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