Answers

Add 80/21 and 28/80

1^st number: 3 17/21, 2^nd number: 28/80

80/21 + 28/80 is 1747/420.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 80 is 1680
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1680
2. For the 1st fraction, since 21 × 80 = 1680,
   80/21 = 80 × 80/21 × 80 = 6400/1680
3. Likewise, for the 2nd fraction, since 80 × 21 = 1680,
   28/80 = 28 × 21/80 × 21 = 588/1680
4. Add the two like fractions:
   6400/1680 + 588/1680 = 6400 + 588/1680 = 6988/1680
5. 6988/1680 simplified gives 1747/420
6. So, 80/21 + 28/80 = 1747/420
   In mixed form: 467/420

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