Suppose $x$ is a uniform random variable with $c = 20$ and $d = 90$. Find the standard deviation of $x$.
A) $\sigma = 31.75$
B) $\sigma = 2.42$
C) $\sigma = 3.03$
D) $\sigma = 20.21$

Question

Quizplus · Accepted Answer

The standard deviation of a uniform distribution is given by $\sigma = \frac{d-c}{\sqrt{12}}$. Substituting $c = 20$ and $d = 90$, we get $\sigma = \frac{90-20}{\sqrt{12}} = \frac{70}{\sqrt{12}} \approx 20.21$.

Suppose xxx Is a Uniform Random Variable With c=20c = 20c=20 And d=90d = 90d=90

Suppose $x$ Is a Uniform Random Variable With $c = 20$ And $d = 90$