Answers

Add 72/84 and 28/80

72/84 + 28/80 is 169/140.

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,
   72/84 = 72 × 20/84 × 20 = 1440/1680
3. Likewise, for the 2nd fraction, since 80 × 21 = 1680,
   28/80 = 28 × 21/80 × 21 = 588/1680
4. Add the two like fractions:
   1440/1680 + 588/1680 = 1440 + 588/1680 = 2028/1680
5. 2028/1680 simplified gives 169/140
6. So, 72/84 + 28/80 = 169/140
   In mixed form: 129/140

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