Answers

Add 5/25 and 81/21

1^st number: 5/25, 2^nd number: 3 18/21

5/25 + 81/21 is 142/35.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 25 and 21 is 525
   
   Next, find the equivalent fraction of both fractional numbers with denominator 525
2. For the 1st fraction, since 25 × 21 = 525,
   5/25 = 5 × 21/25 × 21 = 105/525
3. Likewise, for the 2nd fraction, since 21 × 25 = 525,
   81/21 = 81 × 25/21 × 25 = 2025/525
4. Add the two like fractions:
   105/525 + 2025/525 = 105 + 2025/525 = 2130/525
5. 2130/525 simplified gives 142/35
6. So, 5/25 + 81/21 = 142/35
   In mixed form: 42/35

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