Question

Please Help!!!! Fan and Medal!!!!

Answer 1

@Vandreigan

Answer 2

Are you familiar with each of these types of sampling?

Answer 3

no

Answer 4

Is it C.

Answer 5

Convenience sampling is where you choose samples that are the most convenient for you to choose. The first 10 people you see walking down the street outside, for instance.

Stratified Random Sampling is where you get a nice, distributed sample, but there are sub groups. You divide your sample up into these sub groups first.

Systematic sampling is where you choose a random starting point, and then skip over so many before acquiring your next data point. For instance, starting at number 5 on a list, and then skipping 7 each time to get your next data point.

Voluntary response is a sample of just whoever responds.

Yes, this is an example of systematic sampling :)

Answer 6

@Vandreigan
A candidate for city council wants to determine how much support she has among the voters in her district by conducting a survey.


Which sampling method will most likely result in a biased sample?

A.
The candidate selects every fifth name on a list of registered voters in her district.

B.
The candidate randomly selects 100 voters in each of the five wards in her district.

C.
The candidate surveys the first 100 people who pass by her campaign headquarters.

D.
The candidate uses a computer program to randomly generate names of voters in her district.

Answer 7

Which of these sampling processes would cause her to only get people who are a lot like one another?

Answer 8

D.

Answer 9

Not D. Random is good!

The first 100 people who pass by her campaign headquarters, however, are all in the same geographic location. Depending on where the HQ is, they likely all work in the same area, live in the same area, etc. I'd choose that one, as it seems to sample the least amount of her voting base.

Answer 10

so C.

Answer 11

Yep, C :)

Answer 12

A manufacturer of springs tests a random sample of 150 springs and finds that 2 springs fail a stress test. The manufacturer will ship 5000 springs in its next shipment.


What is the best prediction for the number of springs in the next shipment that will fail under stress?

A.
67

B.
75

C.
133

D.
150

Answer 13

@Vandreigan

Answer 14

What percentage of springs that were tested failed the stress test?

Answer 15

i dont know

Answer 16

150 were tested. 2 failed. The percentage that failed is then: 2/150

Answer 17

We expect this to be representative of the whole, so we expect this percentage of a shipment to fail. So, we just multiply the size of the shipment by this percentage to find the number that we expect to fail.

5000 * 2/150 = ?

Answer 18

66 2/3

Answer 19

Yep. Round that, and you're done

Answer 20

can you help me to round it

Answer 21

Is it closer to 67 or to 66?

Answer 22

67

Answer 23

Yep. So 66 2/3 rounds to 67