Answers

Add 80/42 and 81/72

1^st number: 1 38/42, 2^nd number: 1 9/72

80/42 + 81/72 is 509/168.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 72 is 504
   
   Next, find the equivalent fraction of both fractional numbers with denominator 504
2. For the 1st fraction, since 42 × 12 = 504,
   80/42 = 80 × 12/42 × 12 = 960/504
3. Likewise, for the 2nd fraction, since 72 × 7 = 504,
   81/72 = 81 × 7/72 × 7 = 567/504
4. Add the two like fractions:
   960/504 + 567/504 = 960 + 567/504 = 1527/504
5. 1527/504 simplified gives 509/168
6. So, 80/42 + 81/72 = 509/168
   In mixed form: 35/168

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