Answers

Add 84/90 and 81/42

1^st number: 84/90, 2^nd number: 1 39/42

84/90 + 81/42 is 601/210.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 42 is 630
   
   Next, find the equivalent fraction of both fractional numbers with denominator 630
2. For the 1st fraction, since 90 × 7 = 630,
   84/90 = 84 × 7/90 × 7 = 588/630
3. Likewise, for the 2nd fraction, since 42 × 15 = 630,
   81/42 = 81 × 15/42 × 15 = 1215/630
4. Add the two like fractions:
   588/630 + 1215/630 = 588 + 1215/630 = 1803/630
5. 1803/630 simplified gives 601/210
6. So, 84/90 + 81/42 = 601/210
   In mixed form: 2181/210

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