Answers

Add 28/84 and 20/72

28/84 + 20/72 is 11/18.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 72 is 504
   
   Next, find the equivalent fraction of both fractional numbers with denominator 504
2. For the 1st fraction, since 84 × 6 = 504,
   28/84 = 28 × 6/84 × 6 = 168/504
3. Likewise, for the 2nd fraction, since 72 × 7 = 504,
   20/72 = 20 × 7/72 × 7 = 140/504
4. Add the two like fractions:
   168/504 + 140/504 = 168 + 140/504 = 308/504
5. 308/504 simplified gives 11/18
6. So, 28/84 + 20/72 = 11/18

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