Answers

Add 45/42 and 21/81

1^st number: 1 3/42, 2^nd number: 21/81

45/42 + 21/81 is 503/378.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 81 is 1134
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1134
2. For the 1st fraction, since 42 × 27 = 1134,
   45/42 = 45 × 27/42 × 27 = 1215/1134
3. Likewise, for the 2nd fraction, since 81 × 14 = 1134,
   21/81 = 21 × 14/81 × 14 = 294/1134
4. Add the two like fractions:
   1215/1134 + 294/1134 = 1215 + 294/1134 = 1509/1134
5. 1509/1134 simplified gives 503/378
6. So, 45/42 + 21/81 = 503/378
   In mixed form: 1125/378

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