states in the fall of 1998
state---------- number of public secondary schools
Florida------------------456
Georgia----------------306
Maine-------------------160
Massachusetts------363
North Carolina-------376
New york--------------935
Rhode Island---------54
Virginia-----------------349
1) 1) Find the mean, median,model, and standard deviation of the data. round to the nearest hundredth, if necessary
2) Determine weather the data in the table appears to be positively skewed, or normally distributed. Explain
3) the time a group of high school students arrive home from school each day was found to be normally distributed. the mean time was 3:15 PM and the time has a standard deviation for 15 minutes. What is the probability that a student chosen at random arrives home from school before 2:30 PM?Can you help me on this table please!!!! can u help me answer this for review#16 ?
PROBLEM 1:
Mean:
456 + 306 + 160 + 363 + 376 + 935 + 54 + 349 = 2999
2999/8 = 374.875 = 374.9
Median:
54, 160, 306, 349, 363, 376, 456, 935
349 + 363 = 712
712/2 = 356
Mode:
None
Standard Deviation:
x...........x-374.9........(x-374.9)^2
54.........-320.9..........102,976.81
160.......-214.9..........46,182.01
306.......-68.9............4,747.21
349.......-25.9............670.81
363.......-11.9............141.61
376........1.1..............1.21
456........81.1............6,577.21
935........560.1..........313,712.01
................................475,00鈥?br>
Add all of the values in the last column together.
Divide that number by (8 - 1) or 7
475008.88/7 = 67585.411
Then take the square root of that number
鈭?7585.411 = 260.496
260.5 = Standard Deviation
PROBLEM 2:
I am not really sure what this question is asking. I have a feeling you will have to calculate a z-score or something but I thought that had to give you a value to test to do that.
x...........x-374.9........(x-374.9)/2鈥?br>
54.........-320.9..........-1.232
160.......-214.9..........-0.825
306.......-68.9............-0.2645
349.......-25.9............-0.0994
363.......-11.9............-0.0457
376........1.1..............0.00422
456........81.1............0.31132
935........560.1..........2.1501
PROBLEM 3:
I don't know how to solve it because in my math we never learned about normally distribution.
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