Understand Z-Score Table & Outliers Impact on Mean

[F.B]

My textbook has the z-score table but it doesn't explain why the sign or magnitude means. It automatically assumes that we know.
I tried searching for this information but i can't find it.

1. Explain why do normal score tables typically not include z values greater than 2.99.

So can anyone give me the link to some sites that contain this type of information.

2. Explain why an outlier affects the mean more than the median or mode.

Is it because the mean changes with the data. If you change some of the values then the mean will also change but the mode and median should remain roughly the same.

 

[andrewchang]

an outlier affect the mean more because the value of it is taken into account as opposed to the median, where the position of it is simply taken into account (moving the median less than the mean would move)