Answers

Add 84/21 and 42/72

1^st number: 4 0/21, 2^nd number: 42/72

84/21 + 42/72 is 55/12.

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,
   84/21 = 84 × 24/21 × 24 = 2016/504
3. Likewise, for the 2nd fraction, since 72 × 7 = 504,
   42/72 = 42 × 7/72 × 7 = 294/504
4. Add the two like fractions:
   2016/504 + 294/504 = 2016 + 294/504 = 2310/504
5. 2310/504 simplified gives 55/12
6. So, 84/21 + 42/72 = 55/12
   In mixed form: 47/12

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