Statistics for homework

IPhone apps For the population of individuals who own
an iPhone, suppose p = 0.25 is the proportion that has a
given app. For a particular iPhone owner, let x = 1 if they
have the app and x = 0 otherwise. For a random sample
of 50 people who have an iPhone:

a. State the population distribution (that is, the probability
distribution of X for each observation).

b. Find the mean of the sampling distribution of the sample
proportion who have the app among the 50 people.

c. Find the standard deviation of the sampling distribution
of the sample proportion who have the app among
the 50 people.

d. Explain what the standard deviation in part c
describes.

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TOPICS
1 Data and Data Sets (classifying data: nominal, ordinal, interval, ratio, etc.)
2 Displaying Data (bar charts, pie charts, histograms, etc.)
3 Numerical Summaries (mean, median, mode, variance, etc.)
4 Relationships between two variables
5 Introduction to Probability
6 Probability Distributions (Binomial, Poisson, Normal)
7 Sampling & Sampling Distributions
8 Interval Estimation (1 sample & 2 sample)
9 Hypothesis Testing (1 sample)
10 Hypothesis Testing (2 sample) Including Chi-Square test for independence
11 Regression Analysis (Simple linear & Multiple linear)
12 Revision (3 Trial Exams & Detailed Solutions)