# Problem#20

Probability Level 3

A child had to calculate $\dbinom{n+k-1}{3}$ but instead he calculated $\dbinom{n+k}{4}$. Interestingly both the answers were same. What is the maximum possible value of $\dbinom{n+4}{k}\times\dbinom{k+3}{k+1}$. You may use a calculator for a final step. Given $n$ and $k$ are whole numbers.

This problem is a part of the series <One minute problems>

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