According to a (somewhat) recent Digital Trends article, 43% of all U.S. cellphone users are iPhone users.

According to a (somewhat) recent Digital Trends article, 43% of all U.S. cellphone users are iPhone users. You believe this value is too low. You randomly select 100 of your peers that have cellphones and have determined that 52% of your sample are iPhone users. What is the probability of randomly selecting 100 cellphone users where the proportion who are iPhone users is more than 0.52?

a. What type of distribution are you using? Pick one of the following: “uniform distribution,” “normal distribution,” “sampling distribution for ?̅,” and “sampling distribution for ?̂.”

b. Is the distribution normal? How do you know?

c. What are the mean and standard deviation of your distribution?

d. Sketch a picture, shade, then find the probability of randomly selecting 100 cellphone users where the proportion who are iPhone users is more than 0.52.

e. Look at your answer from part d. You collect another sample of 100 people and calculate the proportion of them who are iPhone users, would you expect to get similar results to what you saw (52% of your sample being iPhone users)?

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orchestra answered 1 year ago

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