Answers

Add 9/54 and 21/42

9/54 + 21/42 is 2/3.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 54 and 42 is 378
   
   Next, find the equivalent fraction of both fractional numbers with denominator 378
2. For the 1st fraction, since 54 × 7 = 378,
   9/54 = 9 × 7/54 × 7 = 63/378
3. Likewise, for the 2nd fraction, since 42 × 9 = 378,
   21/42 = 21 × 9/42 × 9 = 189/378
4. Add the two like fractions:
   63/378 + 189/378 = 63 + 189/378 = 252/378
5. 252/378 simplified gives 2/3
6. So, 9/54 + 21/42 = 2/3

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