SOLUTION: According to the Internal Revenue Service, the mean tax for the year 2011 was $3,000. Assume the standard deviation is $410 and that the amounts follow a normal probability distr

Algebra ->  Probability-and-statistics -> SOLUTION: According to the Internal Revenue Service, the mean tax for the year 2011 was $3,000. Assume the standard deviation is $410 and that the amounts follow a normal probability distr      Log On


   

Question 646174: According to the Internal Revenue Service, the mean tax for the year 2011
was $3,000. Assume the standard deviation is $410 and that the amounts follow
a normal probability distribution.
What percent of the refunds are less than $2,900 or greater than $3,200?
Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!
 

Hi,

mean tax for the year 2011 was $3,000. Assume the standard deviation is $410

Using TI-83 Calculator to Probability Distribution Values Normal

Press 2nd VARS [DISTR].Scroll down to 2:normalcdf and Press ENTER.

Enter data and Press ENTER.

 P(x < 2900 or > 3200) = 1 - P(2900 ≤ x ≤ 3200)

                       = 1- normalcdf(2900, 3200, 3000, 410)