Objective 10

Standard deviationBy: Joey Slack

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The # of absentees per day at Jackson elementary school is believed to be an approximately normal distribution, with a mean of 143 absentees/day and a standard deviation of 20 absentees per day use the table to determine the approximate probability the fewer than 123 absences will occur any given day!!!

First go on your calculator and press 2nd-vars-2 That will bring you to the screen that says (Normal cdf)

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After you bring up the page then you need to know the mean (in this case it is 161).You also need to know the standard deviation (in this case it is 12).When you have this question is using the lowest possible number to the 149. When you enter this it should look like this:

Lowest possible = -infinity e99Highest possible = +infinity e99

After you press enter it will take you to a number And this number is not always right on to the answer just pick the closest one.

Part 2

Start with stat then enter type into L1 the #s that the question has in this case it is 3,7,9,11,15.

Then we have to go to the main page on your calculator then press stat then over to the right then –var stats. Then enter.

Then u will need to put in list 1 by pressing 2nd 1.

Find the standard deviation for the data given 3,7,9,11,15Population standard deviation.

Sample standard deviation.

In this question we use the population standard deviation

Part three

3247

31 + 47 = 79

Now you need to type this in your calculator.

Left- 200Right-252Mean-200S D -26

To do this you need to get into (normalcdf)To do this press 2nd-vars-down-enter.

Left- 200Right-252Mean-200S D -26

You need to enter this in this order!!

Hit enter and you will have your answer!!

Take this and multiply it by the amount of kids (500)

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