Probability density function of a random variable $X$ is given below
$$f(x) = \begin{cases} 0.25 & \text{ if } 1 \leq x \leq 5 \\ 0 & \text{ otherwise} \end{cases}$$
$P(X \leq 4)$ is
- $\dfrac{3}{4} \\$
- $\dfrac{1}{2} \\$
- $\dfrac{1}{4} \\$
- $\dfrac{1}{8}$