Answers

Add 21/84 and 72/18

1^st number: 21/84, 2^nd number: 4 0/18

21/84 + 72/18 is 17/4.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 18 is 252
   
   Next, find the equivalent fraction of both fractional numbers with denominator 252
2. For the 1st fraction, since 84 × 3 = 252,
   21/84 = 21 × 3/84 × 3 = 63/252
3. Likewise, for the 2nd fraction, since 18 × 14 = 252,
   72/18 = 72 × 14/18 × 14 = 1008/252
4. Add the two like fractions:
   63/252 + 1008/252 = 63 + 1008/252 = 1071/252
5. 1071/252 simplified gives 17/4
6. So, 21/84 + 72/18 = 17/4
   In mixed form: 41/4

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