Question

(URGENT-15 Points) Can someone help me/check my answers for this? Thank you! For the first screenshot, my answers for 1-5 are: (1) 79.2 (2) 12.4 (3) 78 and 82 (4) 76 and 84 (5) 74 and 86. I am stuck on questions 6-8 (#8 is on the second screenshot at the top...). On the second screenshot, I'm not sure how to answer question (9) based on the dot-plot on the first screenshot. For (10), if it's asking for the mean of these numbers, I got 23.8. If it's just asking for the sum, I got 119. For 11-12, the means aren't the same because this mean (#10) is based on the random sample generated from the original number of grades, while the first mean (#2) was based on the total population of grades for the entire class. It would make sense that the second mean would be smaller than the first. I'm giving away 15 points to the person who can help me with this and check my answers! I'd really appreciate it! :)

Answer 1

1.  81.72
2.  10.37
3.  81.72 + 10.37 = 92.09  81.72 - 10.37 = 71.35
4.  81.72 + 2(10.37)= 102.46  81.72 - 2(10.37) = 60.98
5. 81.72 + 3(10.37) = 112.83  81.72-3(10.37) = 50.61
6. no
7. It is not bell-shaped
8.  P(>=90) = 15/50 = 3/10 = 30%; 2nd way??
9.  5 = 68, 12 = 72, 24 = 82, 35 = 89, 43 = 92
10. 80.6
11.  no
12.  The population mean includes all of the data values and the sample mean only includes the 5 data values.