Question:
If ²⁰Cᵣ = ²⁰Cᵣ-₁₀, then ¹⁵Cᵣ is equal to:
If ²⁰Cᵣ = ²⁰Cᵣ-₁₀, then ¹⁵Cᵣ is equal to:
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Use symmetry property ⁿCᵣ = ⁿCₙ-ᵣ.
Updated On: Mar 18, 2026
- 4896
- 816
- 1632
- None of these
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Verified By Collegedunia
The Correct Option is B
Solution and Explanation
Step 1: Using property of combinations. ²⁰Cᵣ = ²⁰C₂₀-ᵣ r-10 = 20-r r = 15
Step 2: Calculation. ¹⁵C₂ = 105 ¹⁵C₁₃ = 105 ¹⁵Cᵣ = 816
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