Answers

Add 70/21 and 80/72

1^st number: 3 7/21, 2^nd number: 1 8/72

70/21 + 80/72 is 40/9.

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,
   70/21 = 70 × 24/21 × 24 = 1680/504
3. Likewise, for the 2nd fraction, since 72 × 7 = 504,
   80/72 = 80 × 7/72 × 7 = 560/504
4. Add the two like fractions:
   1680/504 + 560/504 = 1680 + 560/504 = 2240/504
5. 2240/504 simplified gives 40/9
6. So, 70/21 + 80/72 = 40/9
   In mixed form: 44/9

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