Answers

Add 21/84 and 81/70

1^st number: 21/84, 2^nd number: 1 11/70

21/84 + 81/70 is 197/140.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 70 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 70 × 6 = 420,
   81/70 = 81 × 6/70 × 6 = 486/420
4. Add the two like fractions:
   105/420 + 486/420 = 105 + 486/420 = 591/420
5. 591/420 simplified gives 197/140
6. So, 21/84 + 81/70 = 197/140
   In mixed form: 157/140

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