Answers

Add 15/18 and 8/21

15/18 + 8/21 is 17/14.

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,
   15/18 = 15 × 7/18 × 7 = 105/126
3. Likewise, for the 2nd fraction, since 21 × 6 = 126,
   8/21 = 8 × 6/21 × 6 = 48/126
4. Add the two like fractions:
   105/126 + 48/126 = 105 + 48/126 = 153/126
5. 153/126 simplified gives 17/14
6. So, 15/18 + 8/21 = 17/14
   In mixed form: 13/14

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