It is a Lab for a Stat243 on excel

 The salaries in a certain population are normally distributed with mean $57,873 and standard deviation $3,427. Find the probability that a person has a salary below $48,000. Find the probability that a person’s salary is between $50,000 and $60,000. Find the probability of seeing a salary over $63,500. Find the 90th percentile of the salaries. Find the 25th percentile of the salaries. Do you think that salaries would follow a symmetric, bell-shaped distribution? In your own words, ex- plain why or why not. Format all of your answers to 6 decimal places (in order to show that you used Excel, and not the tables). 

You must do your own work. Make sure to answer the final questions in your own words.

Do not simply copy the examples. The real assignment is at the end.

In Excel, normal probabilities are found using
the NORMDIST function. Click in a blank cell
where you want your answer to appear, click on
the “insert function” icon, fx, and then select
NORMDIST from the statistical menu. This will
give you the cumulative probability, that is, the
area under the curve from negative infinity to the
x value you enter. You may need to subtract the
answer from 1, or subtract two answers, depend-
ing on the problem.

For example, suppose 8  and 2  . To
compute P( 10)X  ,you would enter

=NORMDIST(10,8,2,1)

Note that the last argument of the NORMDIST
function should always be “1”.

To find P( 10)X  in the same example you
would enter

=1-NORMDIST(10,8,2,1)

To find P(10 12)X  , you would enter

= NORMDIST(12,8,2,1)-NORMDIST(10,8,2,1)

Lab 4: The Normal Distribution
Stat 243 Fall 2013 due November 21

In Excel, normal percentiles are found using the
NORMINV function. Click in a blank cell where
you want your answer to appear, click on the
“insert function” icon, fx, and then select
NORMINV from the statistical menu. This will
give you the x value corresponding to the de-
sired cumulative probability.

In the previous example, suppose we wanted to
find the 90th percentile of the distribution. Then
we would enter

=NORMINV(.9,8,2)

Lab 4 (due Thursday, November 21)

The salaries in a certain population are normally distributed with mean $57,873 and standard deviation
$3,427.

1. Find the probability that a person has a salary below $48,000.

2. Find the probability that a person’s salary is between $50,000 and $60,000.

3. Find the probability of seeing a salary over $63,500.

4. Find the 90th percentile of the salaries.

5. Find the 25th percentile of the salaries.

6. Do you think that salaries would follow a symmetric, bell-shaped distribution? In your own words, ex-
plain why or why not.

Format all of your answers to 6 decimal places (in order to show that you used Excel, and not the tables).