Answers

Add 28/84 and 20/80

28/84 + 20/80 is 7/12.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 80 is 1680
   
   Next, find the equivalent fraction of both fractional numbers with denominator 1680
2. For the 1st fraction, since 84 × 20 = 1680,
   28/84 = 28 × 20/84 × 20 = 560/1680
3. Likewise, for the 2nd fraction, since 80 × 21 = 1680,
   20/80 = 20 × 21/80 × 21 = 420/1680
4. Add the two like fractions:
   560/1680 + 420/1680 = 560 + 420/1680 = 980/1680
5. 980/1680 simplified gives 7/12
6. So, 28/84 + 20/80 = 7/12

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