Help me solve all these problems

1. The following are ACT scores are from a sample of 6 randomly selected students at Delta State.

X

22

27

25

20

23

24

a. Calculate the Standard Deviation for the sample (use the space next to the data to show your work).

b. Using the average and your calculated standard deviation, what would a student’s z score be who scored 25?

c. Using that z score, what percentage of students scored above and below that z-score?

2. The average weight of a pumpkin is 14 lbs, σ= 3 lbs. If my dog Loki weighs 16.5 lbs (µ= 16, σ=2), how much would he weigh as a pumpkin?

Conceptual Questions:

3. Buzzfeed posted the following scale:

Is this measure reliable, valid, both, or neither? Why or why not?

4. On scale of 1-10, 10 being “I’m acing this, easy!” and 1 being “honestly at this point I’m just trying to finish” how are you feeling about this exam?

a. What scale of measurement is this and what measure of central tendency would you use for this data?

5. A population has a mean of µ= 50, and a standard deviation of σ=20. Would a score of X = 70 be considered an extreme score (out in the tail)?

6. On an exam with a mean of 39, you obtain a score of X= 35. Would you prefer a standard deviation of 2 or 8? Explain your answer.

Extra Credit:

1. (+3 extra credit):

a. If you multiple each score by 2, what happens to the mean? To the standard deviation?

b. If you add 2 to each score, what happens to the mean? To the standard deviation?

Draw a picture of how you feel right now(+1 extra credit):