Answers

Add 8/18 and 9/21

8/18 + 9/21 is 55/63.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 18 and 21 is 126
   
   Next, find the equivalent fraction of both fractional numbers with denominator 126
2. For the 1st fraction, since 18 × 7 = 126,
   8/18 = 8 × 7/18 × 7 = 56/126
3. Likewise, for the 2nd fraction, since 21 × 6 = 126,
   9/21 = 9 × 6/21 × 6 = 54/126
4. Add the two like fractions:
   56/126 + 54/126 = 56 + 54/126 = 110/126
5. 110/126 simplified gives 55/63
6. So, 8/18 + 9/21 = 55/63

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