Hello everyone,

in this video, we will learn how to use the statistics worksheet in the BA II Plus

financial calculator to compute the sample mean and standard deviation for

the given data set. BA II Plus uses two worksheets to perform a statistical

analysis: the DATA worksheet to enter the data and

STAT worksheet to perform statistical analysis. First we need to access the data worksheet. Data worksheet is the secondary function

on number seven so we're gonna press second

and seven. Just like any other worksheet before entering data points

we need to clear the previous values stored in the worksheet

note that clearing data worksheet will automatically

clear stat worksheet as well. So we press second and then clear.

Now let's enter the values. Because we are using one-variable analysis,

we only key in values for X input variables and

skip Ys as our data don't have a second attribute or y

values. That being said, Y input variable can be used to indicate

frequency if any number is repeated in the set.

For example,

in our example uh seven percent is repeated three times and therefore

instead of keying in 7 three times, we can set

Y to 3 to tell the calculator that there are

three 7s in the set. Our first data value

is seven so I key in 7 and I press enter. I use the down arrow

key to go to Y01. Y01,

as I said, we can use it to indicate the frequency

of a particular number that is repeated in the set in this case

seven percent is repeated three times so I can just enter three to tell the calculator that

seven percent is repeated three times in the set.

Now we use a down arrow key to move on to the second entry

X02 is our second data point, in this case 11, 11%.

So I'm going to

press 11 and then press enter. Eleven percent is

repeated once so all I need to do is just press the

down arrow key twice to skip the Y entry. X03 represents the

third variable, in this case three percent,

so I press three and enter again three is repeated once so i can

just skip Y03 entry by pressing the down

arrow key twice. Finally the last value is nine percent

so I press nine and press enter.

Now we are done entering the values. All we need to do

is to exit the data worksheet and enter the stat worksheet. In order to exit the

data worksheet, we press 2ND and we press CPT to

quit the worksheet.

STAT worksheet is used to access

statistical variables and see the results.

It is the secondary function on key number eight,

so I press 2ND and press 8. The first variable in the sheet

indicates whether we are doing one-variable or two-variable statistics.

Except for the first variable, the rest of the

variables are auto-computed. The default setting is one-variable (1-V) and

this is what we are performing. So we go to the second variable

in the sheet by using the down arrow key.

So we press down-arrow key. As you can see n is already been computed and represents

the number of observations or data values in the set, which is six. Now if you use it down arrow again

X bar represents the mean of the values in the set,

in this case 7.33…

We use the down arrow key to move to

sample the standard deviation. S sub x represents sample standard

deviation, which we're looking for in this case. So

the sample standard deviation is 2.66% rounded off the two decimal places. We you use a down arrow key again. Sigma sub x represents population

standard deviation. In case the given values are

the whole population, we'd use this standard deviation.

We use a down arrow key. Sigma x is the sum of the X values, and if I use it down arrow, the last

variable in the worksheet is sigma X square, which is the sum of

the X squared values. To answer the

given problem the mean of the sample is seven point three three percent

rounded off the two decimal places and the standard deviation of the sample

is 2.66 rounded off to two decimal places..