Suppose the true proportion of people who use public transportation to get to work in the Washington, D.C., area is 0.45In a simple random sample of 250people who work in Washington , what is the standard deviation of the sampling distribution of p^?

(a) 0.4975

(b)0.2475

(c) 0.0315

(d) 0.0009

(e) 0.617

Short Answer

Expert verified

The standard deviation of the sampling distribution of p^ is (c)0.0315

Step by step solution

01

Given information

We are given that a sample of 250people who work in Washington with proportion of 0.45. We have to find standard deviation.

02

Simplify

As we know, the standard deviation is composed of true probability and sample size.

SD=p×1-pnSD=0.451-0.45250SD=0.0315

Where,

SD=standard deviation

p=true proportion

n=total sample

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