Answers

Add 45/18 and 80/21

1^st number: 2 9/18, 2^nd number: 3 17/21

45/18 + 80/21 is 265/42.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 18 and 21 is 126
   
   Next, find the equivalent fraction of both fractional numbers with denominator 126
2. For the 1st fraction, since 18 × 7 = 126,
   45/18 = 45 × 7/18 × 7 = 315/126
3. Likewise, for the 2nd fraction, since 21 × 6 = 126,
   80/21 = 80 × 6/21 × 6 = 480/126
4. Add the two like fractions:
   315/126 + 480/126 = 315 + 480/126 = 795/126
5. 795/126 simplified gives 265/42
6. So, 45/18 + 80/21 = 265/42
   In mixed form: 613/42

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