Answers

Add 81/42 and 15/30

1^st number: 1 39/42, 2^nd number: 15/30

81/42 + 15/30 is 17/7.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 30 is 210
   
   Next, find the equivalent fraction of both fractional numbers with denominator 210
2. For the 1st fraction, since 42 × 5 = 210,
   81/42 = 81 × 5/42 × 5 = 405/210
3. Likewise, for the 2nd fraction, since 30 × 7 = 210,
   15/30 = 15 × 7/30 × 7 = 105/210
4. Add the two like fractions:
   405/210 + 105/210 = 405 + 105/210 = 510/210
5. 510/210 simplified gives 17/7
6. So, 81/42 + 15/30 = 17/7
   In mixed form: 23/7

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