Answers

Add 21/12 and 45/20

1^st number: 1 9/12, 2^nd number: 2 5/20

21/12 + 45/20 is 4/1.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 12 and 20 is 60
   
   Next, find the equivalent fraction of both fractional numbers with denominator 60
2. For the 1st fraction, since 12 × 5 = 60,
   21/12 = 21 × 5/12 × 5 = 105/60
3. Likewise, for the 2nd fraction, since 20 × 3 = 60,
   45/20 = 45 × 3/20 × 3 = 135/60
4. Add the two like fractions:
   105/60 + 135/60 = 105 + 135/60 = 240/60
5. 240/60 simplified gives 4/1
6. So, 21/12 + 45/20 = 4/1

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