SOLUTION: Dear madam/sir How to calculate Z raw value when the area between two variables are given in normal distribution ?

Algebra ->  Probability-and-statistics -> SOLUTION: Dear madam/sir How to calculate Z raw value when the area between two variables are given in normal distribution ?      Log On


   

Question 1185602: Dear madam/sir
How to calculate Z raw value when the area between two variables are given in normal distribution ?
Answer by Theo(13342) About Me  (Show Source):
You can put this solution on YOUR website!
the area is between two z-scores.\

you find the area to the left of the high score and you find the area to the left of the low score.

you subtract the smaller area from the larger area.

that's the area in between.

example:

you want to find the area between z-score of 0.5 and 2.0

find the area to the left of the z-score of 2 and find the area to the left of z-score .5.

i used the following z-score table.

http://www.z-table.com/

the area to the left of a z-score of 2 is equal to .9775.
the area to the left of a z-score of .5 is equal to .6915.

the area between those two z-score is equal to .9775 minus .6915 = .2860 per the value in the tables.

you could also use an online calculator that gives you the same answer with less effort.

the ti-84 plus calculator that i use would tell you that the area between them is equal to .2857874702.

the following online calculator would tell you that the area in between is equal to .286.

https://stattrek.com/online-calculator/normal.aspx

the following online calculator would tell you that the area in between is equal to .2858.

https://davidmlane.com/hyperstat/z_table.html

the following online calculator would tell you that the area in between is equal to .285788.

https://www.statskingdom.com/normal.html

some calculators can get you the answer directly.
most get you the area to the left of the indicated z-score.
you have to subtract the saller area from the larger area to the left of the indicated z-scores to get the area in between.

the last calculator i showed you said that the area to the left of a z-score of 2 is equal to .97725 and the area to the left of a z-score of .5 is equal to .691462.

subtracting the smaller area from the larger area gets you an area of .285788.

the z-score of .5 and 2 were just used as an example.

if you are still not sure what to do, let me know what the problem is and i'll work it for you with an explanation of what i did.