Question

in a certain town there are 30000 registered voters, of whom 12000 are Democrats. A survey organization is about to take a simple random sample of 1000 registered voters. a) the expected value for the percentage of Democrats in the sample is

Answer 1

400.

Explanation:

The following data were obtained from the question:

Total number of Registered voters = 30000

Total number of Democrats = 12000

Next, we shall determine the percentage of Democrats in the registered voters.

This can be obtained as follow:

Percentage of Democrats = number of Democrats / Total number of registered voters x 100

Percentage of Democrats = 12000/30000 x 100

Percentage of Democrats = 40%

Now, we can obtain the expected value of percentage of Democrats in the 1000 sample as follow:

Percentage of Democrats = 40%

Total number of Sample = 1000

Number of Democrats in the sampl=..?

Percentage of Democrats = number of Democrats in sample / Total number of sample x 100

40% = number of Democrats in sample/1000

Cross multiply

Number of Democrats in sample

= 40% x 1000

= 40/100 x 1000

= 400

Therefore, the expected number of Democrats in the sample is 400.