Mathematics · 2019
JEE Main · 10 January 2019, Shift 1 · Q66
If Σ_i=1^20((^20 C_i-1)/(^20 C_i+^20 C_i-1))^3=k/21, then k equals:
If $\displaystyle \sum_{i=1}^{20}\left(\frac{{ }^{20} \mathrm{C}_{i-1}}{{ }^{20} \mathrm{C}_i+{ }^{20} \mathrm{C}_{i-1}}\right)^3=\frac{k}{21}$, then $\displaystyle k$
equals :
Official answer
(2)
$\displaystyle 100$
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JEE Main 2019 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.