Question

An investment website can tell what devices are used to access their 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. They draw a random sample of 428 investors from their customers. Suppose that the true proportion of smartphone users is 39%. Complete parts a) through c) below. a) What would the managers expect the shape of the sampling distribution for the sample proportion to be? Skewed to the right Nonsymmetric Unimodal and symmetric Skewed to the left Vies My b) What would be the mean of this sampling distribution? Mean(Round to two decimal pladas as needed.) c) What would be the standard deviation of the sampling distribution? Standard Deviation (Round to three decimal places as needed) me.

Answer 1

a. As n is sufficient large so distribution is normal

Hence answer here is

o Unimodal and symmetric

b. Mean value is

Mp=P=0.39

c. Standard deviation is $\sigma_{\widehat{p}}=\sqrt{\frac{\widehat{p}{\widehat{q}}}{n}}=\sqrt{\frac{0.39*0.61}{428}}=0.024$