Answers

Add 90/21 and 84/72

1^st number: 4 6/21, 2^nd number: 1 12/72

90/21 + 84/72 is 229/42.

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,
   90/21 = 90 × 24/21 × 24 = 2160/504
3. Likewise, for the 2nd fraction, since 72 × 7 = 504,
   84/72 = 84 × 7/72 × 7 = 588/504
4. Add the two like fractions:
   2160/504 + 588/504 = 2160 + 588/504 = 2748/504
5. 2748/504 simplified gives 229/42
6. So, 90/21 + 84/72 = 229/42
   In mixed form: 519/42

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