Answers

Add 21/16 and 28/20

1^st number: 1 5/16, 2^nd number: 1 8/20

21/16 + 28/20 is 217/80.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 16 and 20 is 80
   
   Next, find the equivalent fraction of both fractional numbers with denominator 80
2. For the 1st fraction, since 16 × 5 = 80,
   21/16 = 21 × 5/16 × 5 = 105/80
3. Likewise, for the 2nd fraction, since 20 × 4 = 80,
   28/20 = 28 × 4/20 × 4 = 112/80
4. Add the two like fractions:
   105/80 + 112/80 = 105 + 112/80 = 217/80
5. So, 21/16 + 28/20 = 217/80
   In mixed form: 257/80

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