Answers

Add 28/42 and 84/90

28/42 + 84/90 is 8/5.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 42 and 90 is 630
   
   Next, find the equivalent fraction of both fractional numbers with denominator 630
2. For the 1st fraction, since 42 × 15 = 630,
   28/42 = 28 × 15/42 × 15 = 420/630
3. Likewise, for the 2nd fraction, since 90 × 7 = 630,
   84/90 = 84 × 7/90 × 7 = 588/630
4. Add the two like fractions:
   420/630 + 588/630 = 420 + 588/630 = 1008/630
5. 1008/630 simplified gives 8/5
6. So, 28/42 + 84/90 = 8/5
   In mixed form: 13/5

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