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 387 investors from their customers. suppose that the true proportion of smartphone users is 38%. complete parts a. through c. below.

a. what would the managers expect the shape of the sampling distribution for the sample proportion to be?
b. what would be the mean of this sampling distribution?
c. what would be the standard deviation of the samplingdistribution?

a) Normal

b) Mean = 0.38

c) Standard deviation = 0.0247

Step-by-step explanation:

a) The shape of the sampling distraction is normal because the sampling distribution depends on the mean and standard deviation.

b) The mean of the sampling distribution will be equal to the true proportion of smart phone users.

The true proportion of smart phone users = 38% = 0.38

p = 0.38

c) Standard deviation α = √ pq/n

p = 0.38

q = 1 - p

q = 1 - 0.38

= 0.62

n = 387

α = √ (0.38*0.62)/387

= √0.2356/387

= √0.0006087855

= 0.0247

The standard deviation = 0.0247

i think it is everything has to equal 180 so, if i correct 4=c. 6=d. 8=a. 7=b. and the last question would be c. because they are parallel lines and they are congruent.

step-by-step explanation:

the reason everything has to equal to 180 is because that is how it works. i'm guessing that is its rule. 4 and 8 are congruent and parallel so, that would be 30+30 because they have the same number. it would equal 60. 6 and 7 are congruent and parallel so, that would be 30+30 because they have the same number. it would equal 60. 60+60 is 180. so, now you have your answer