Answers

Add 21/84 and 20/54

21/84 + 20/54 is 67/108.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 84 and 54 is 756
   
   Next, find the equivalent fraction of both fractional numbers with denominator 756
2. For the 1st fraction, since 84 × 9 = 756,
   21/84 = 21 × 9/84 × 9 = 189/756
3. Likewise, for the 2nd fraction, since 54 × 14 = 756,
   20/54 = 20 × 14/54 × 14 = 280/756
4. Add the two like fractions:
   189/756 + 280/756 = 189 + 280/756 = 469/756
5. 469/756 simplified gives 67/108
6. So, 21/84 + 20/54 = 67/108

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