If `\ ^(15)C_(3r)=\ ^(15)C_(r+3)`,find r

Explanation

To solve the equation \( \binom{15}{3r} = \binom{15}{r+3} \), we can use the property of combinations that states \( \binom{n}{k} = \binom{n}{n-k} \).

### Step-by-Step Solution:

1. **Set up the equation using the property of combinations**:
\[ \binom{15}{3r} = \binom{15}{r+3} \]
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