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A random sample of n = 250 measurements is drawn from a binomial population with a probability of success of .85.

  1. FindEPÁåžandσpÁåž
  2. Describe the shape of the sampling distribution ofpÁåœ.
  3. Find

Short Answer

Expert verified

Random sampling is a sample strategy in which every sample has an equal probability of being selected. A random sample is intended to provide an impartial reflection of the overall population.

Step by step solution

01

 Step 1: (a) The data is given below

The calculation is given below:

Given,

p=0.85Population Proportion= 1-P=1-0.85=0.15

n=250Sample Size

The sample proportionis pÁåœ.

Mean =μpÁåžP=0.85

SDσpÁåœ=p1-p/ n=0.85×0.15250=0.02258317

μpÁåœ=0.85σpÁåœ=0.02258317

02

(b) The data is given below

The calculation is given below:

Since bothn×p and n×1-pare>=10, so

The pÁåœsampling distribution is about normal.

03

(c) The data is given below

The calculation is given below:

ppÁåœ-μpÁåœ/σpÁåœ<0.9-μpÁåœ/μpÁåœ=PZ<0.9-0.85/0.02258317=PZ<2.21=0.9864...use z table

ppÁåœ<0.9=0.9864

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