Answers

Add 21/20 and 28/80

1^st number: 1 1/20, 2^nd number: 28/80

21/20 + 28/80 is 7/5.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 20 and 80 is 80
   
   Next, find the equivalent fraction of both fractional numbers with denominator 80
2. For the 1st fraction, since 20 × 4 = 80,
   21/20 = 21 × 4/20 × 4 = 84/80
3. Likewise, for the 2nd fraction, since 80 × 1 = 80,
   28/80 = 28 × 1/80 × 1 = 28/80
4. Add the two like fractions:
   84/80 + 28/80 = 84 + 28/80 = 112/80
5. 112/80 simplified gives 7/5
6. So, 21/20 + 28/80 = 7/5
   In mixed form: 12/5

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