Answer Happy

1. An investment website monitors what devices are used to access the site. The site managers wonder whether they should enhance the facilities for trading via smartphones, so they want to estimate the proportion of users who access the site that way (even if they also use their computers sometimes). They draw a random sample of 200 investors from their customers. Suppose that the true proportion of smartphone users is 36%. a. What would you expect the shape of the sampling distribution for the sample proportion to be? b. What would be the mean of this sampling distribution? c. If the sample size were increased to 500, would your answers change? Explain. LO O 3. The investment website in Exercise 10 draws a random sample of 200 investors from its customers. Suppose that the true proportion of smartphone users is 36%. a. What would be the standard deviation of the sampling distribution of the proportion of smartphone users? b. What is the probability that the sample proportion of smartphone users is greater than 0.36? c. What is the probability that it's between 0.30 and 0.40? d. What is the probability that it's less than 0.28? e. What is the probability that it's greater than 0.42? LO