Answers

Add 28/21 and 18/84

1^st number: 1 7/21, 2^nd number: 18/84

28/21 + 18/84 is 65/42.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 84 is 84
   
   Next, find the equivalent fraction of both fractional numbers with denominator 84
2. For the 1st fraction, since 21 × 4 = 84,
   28/21 = 28 × 4/21 × 4 = 112/84
3. Likewise, for the 2nd fraction, since 84 × 1 = 84,
   18/84 = 18 × 1/84 × 1 = 18/84
4. Add the two like fractions:
   112/84 + 18/84 = 112 + 18/84 = 130/84
5. 130/84 simplified gives 65/42
6. So, 28/21 + 18/84 = 65/42
   In mixed form: 123/42

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