Answers

Add 5/21 and 81/72

1^st number: 5/21, 2^nd number: 1 9/72

5/21 + 81/72 is 229/168.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 21 and 72 is 504
   
   Next, find the equivalent fraction of both fractional numbers with denominator 504
2. For the 1st fraction, since 21 × 24 = 504,
   5/21 = 5 × 24/21 × 24 = 120/504
3. Likewise, for the 2nd fraction, since 72 × 7 = 504,
   81/72 = 81 × 7/72 × 7 = 567/504
4. Add the two like fractions:
   120/504 + 567/504 = 120 + 567/504 = 687/504
5. 687/504 simplified gives 229/168
6. So, 5/21 + 81/72 = 229/168
   In mixed form: 161/168

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