## Saylilbaby one year ago help pls

1. saylilbaby

2. saylilbaby

@jim_thompson5910 @Compassionate @Kainui

3. jim_thompson5910

where are you stuck?

4. saylilbaby

i havent started @jim_thompson5910

5. jim_thompson5910

so you're not sure what $$\Large \bar{x}$$ means ?

6. saylilbaby

im not sure how to do anything... this is a summer class i havent learned anything from this...this is a class to get a credit @jim_thompson5910

7. jim_thompson5910

$\Large \bar{x}$ means xbar, this is the sample mean

8. jim_thompson5910

you add up all the numbers in the sample and then divide by the number of numbers

9. jim_thompson5910

so you have to first go through the graph given to you and pull out all of the data values

10. anonymous

Each one of the dots represents an amount of numbers in the set. So if a 60 had 2 dots on it, you would have 2 60's in the sequence. (60, 60, ... ) so continue doing that for all the numbers

11. saylilbaby

is number 1 80? @jim_thompson5910

12. jim_thompson5910

13. saylilbaby

im asking is number 1 80 or 191.47619 @jim_thompson5910

14. jim_thompson5910

the mean isn't either of those values

15. saylilbaby

well can u help @jim_thompson5910

16. jim_thompson5910

did you get these values 60,61,63,65,68,68,68,69,69,70,70,72,74,76,76,76,78,79,80,80,80,80,82,82,82,82,84,85,85,86,86,86,87,88,89,90,90,90,90,90,92,92,92,92,95,95,95,98,99,100 ??

17. jim_thompson5910

there are 50 numbers in that list above (each one pulled from each dot)

18. saylilbaby

yes

19. saylilbaby

80.42 @jim_thompson5910

20. jim_thompson5910

when you added all of the 50 numbers up, what did you get?

21. saylilbaby

4021 @jim_thompson5910

22. jim_thompson5910

you made an error, it should be larger than 4021

23. saylilbaby

4176 and when divided by 50 i got 83.52 @jim_thompson5910

24. jim_thompson5910

4176 is too high

25. saylilbaby

thats wat i keep getting @jim_thompson5910

26. jim_thompson5910

60+61+63+65+68+68+68+69+69+70+70+72+74+76+76+76+78+79+80+80+80+80+82+82+82+82+84+85+85+86+86+86+87+88+89+90+90+90+90+90+92+92+92+92+95+95+95+98+99+100 = 4,086

27. saylilbaby

so 81.72 @jim_thompson5910

28. jim_thompson5910

yes that is xbar

29. saylilbaby

ok wat about number 2 @jim_thompson5910

30. jim_thompson5910

use something like this https://www.easycalculation.com/statistics/standard-deviation.php

31. jim_thompson5910

type in all the numbers separated by commas

32. saylilbaby

ok i did now wat am i looking for in number 2 @jim_thompson5910

33. jim_thompson5910

do you see where it says Standard deviation 10.47259

34. saylilbaby

yes @jim_thompson5910

35. jim_thompson5910

36. saylilbaby

3 4 and 5 @jim_thompson5910 wat i do

37. jim_thompson5910

xbar will be used in place of $$\Large \mu$$ the standard deviation is $$\Large \sigma$$

38. jim_thompson5910

what you need to do is compute 81.72 - k*10.47259 for k = 1, k = 2, and k = 3 also compute 81.72 + k*10.47259 for k = 1, k = 2, and k = 3