In the diagram, $W X Y$ is a straight angle. What is the average (mean) of $p, q, r, s$, and $t$ ?
(A) 30
(B) 36
(C) 60
(D) 72
(E) 45

![](https://cdn.mathpix.com/cropped/2024_04_20_ac36362783317e0251fdg-020.jpg?height=241&width=461&top_left_y=2118&top_left_x=1255)
Since $W X Y$ is a straight angle, then $p^{\circ}+q^{\circ}+r^{\circ}+s^{\circ}+t^{\circ}=180^{\circ}$ and so $p+q+r+s+t=180$.

To calculate the average of $p, q, r, s$, and $t$, we add the five numbers and divide by 5 .

Therefore, the average of $p, q, r, s$, and $t$ is $\frac{p+q+r+s+t}{5}=\frac{180}{5}=36$.

ANSWER: (B)