Answers

Add 21/84 and 81/5

1^st number: 21/84, 2^nd number: 16 1/5

21/84 + 81/5 is 329/20.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 5 is 420
   
   Next, find the equivalent fraction of both fractional numbers with denominator 420
2. For the 1st fraction, since 84 × 5 = 420,
   21/84 = 21 × 5/84 × 5 = 105/420
3. Likewise, for the 2nd fraction, since 5 × 84 = 420,
   81/5 = 81 × 84/5 × 84 = 6804/420
4. Add the two like fractions:
   105/420 + 6804/420 = 105 + 6804/420 = 6909/420
5. 6909/420 simplified gives 329/20
6. So, 21/84 + 81/5 = 329/20
   In mixed form: 169/20

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