Basics of Using the Std Normal Table

Basics of Using the Std Normal Table

Category:

Education

Tags:

• Bowen
• MATH 110
• Normal Distribution

[lbowen11235]

So, for the numbers you refererence here (for z=1.22), the area under the curve from negative infinity to 1.22 is .8888 (as I said) & the area from zero to 1.22 is .3888 (as you said). In other words, if you use a table that starts accumulating from zero, you have to add 0.5 to whatever you get in your table (for z>=0) to get the probablity that I was referencing. (It gets a little more complex for negative z values which is why I don't care for those type of tables.) I hope this answer helps.

[lbowen11235]

Notice: .8888-.3888=.5000. So I think the table you use isn't cumulative from negative infinty to z but from zero to z (for z >=0). I've seen a few texts using tables like that. (You can tell by looking at where the shading starts under the normal curve that usually apprears above the table itself. If the shading begins at zero rather than negative infinity, then you have such a table.)

[CP3clippernation]

in my book z area of 1.22 was 0.3888 not 0.8888. Is this a typo?

[cpowel2]

Thank you for actually explaining what the column headers mean my teacher did not and i failed a quiz because in all the examples in class we used 0.05 based on coincidence so finally someone that doesn't assume every ting

[bubzieboo27]

this is a great explanation!! thanks heaps..

[dekylio]

thanku so much!! i nevr undrstood my teacher!!!

[salmonxia]

videos are sharp ,angle is good. these presentations are way nicer than other people's' which are blurred . thank you for posting .