Answers

Add 8/15 and 7/21

8/15 + 7/21 is 13/15.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 15 and 21 is 105
   
   Next, find the equivalent fraction of both fractional numbers with denominator 105
2. For the 1st fraction, since 15 × 7 = 105,
   8/15 = 8 × 7/15 × 7 = 56/105
3. Likewise, for the 2nd fraction, since 21 × 5 = 105,
   7/21 = 7 × 5/21 × 5 = 35/105
4. Add the two like fractions:
   56/105 + 35/105 = 56 + 35/105 = 91/105
5. 91/105 simplified gives 13/15
6. So, 8/15 + 7/21 = 13/15

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