Probability Distributions

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Let $X$ denote the number of people who enter an elevator on the ground floor of an office building for any randomly observed elevator trip. The elevator can hold no more than $6$ people.

Based on long-term observation, it has been determined that $X$ has the following probability distribution:
$\begin{array}{c|cccccc} x&1&2&3&4&5&6\\ \hline \mathbb{P}(X = x)&0.29&0.25&0.21&0.12&0.08&0.05\\ \end{array}$

What is the probability that at least $4$ people enter the elevator for a randomly observed elevator trip?

$\mathbb{P}(X \geq 4)=$

4. Probability Distributions: Random Variables

Probability Distributions