Probability Theory Question of the Day

Test your knowledge with a hand-picked multiple-choice question.

Let $\up$\text{X}$$ , and $\up$\text{Y}$$ be the lifespans (in hours) of two electronic devices, and their joint probability mass function is given below.

![](https://vt-vtwa-assets.varsitytutors.com/vt-vtwa/uploads/formula_image/image/1030503/gif.latex $"\operatorname{f_{X,Y}$}{\left (x,y \right )} = \begin{cases} c $e^{- 9 x - 11 y}$ & 0<x<y<\infty \ 0, & $\text{Otherwise}$ \end{cases}")

Determine the value of $\up$\text{c}$$ .