Math Is Fun Forum

ladyrain95

Member

Registered: 2013-05-01

Posts: 1

Z-Scores

I am at college level "Math For Liberal Arts".. we are in our last chapter and it's Statistics:

Find the z-score that best satisfies the condition.

14% of the total area is to the left of z.

I thought I understood the basics of this, but I'm frustrated and really confused. Anytime I have to find a number from the "Areas Under the Standard Normal Curve" chart I get the wrong number. I don't know what I'm doing wrong.. can someone please help me?

Last edited by ladyrain95 (2013-05-01 10:11:28)

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Z-Scores

Hi;

http://easycalculation.com/statistics/p … -score.php

Enter in 14 and left tailed and out pops -1.08.

Or use the table here.

http://math2.org/math/stat/distributions/z-dist.htm

It is for below ( to the left ) of a z score. Look for .14. You will find it in row (-1) and column (.08). Answer again is -1.08 standard deviations.

A quick math check:

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In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

stapel

Member

Registered: 2006-07-22

Posts: 15

Re: Z-Scores

I thought I understood the basics of this, but...Anytime I have to find a number from the "Areas Under the Standard Normal Curve" chart I get the wrong number. I don't know what I'm doing wrong.. can someone please help me?

In order to help you figure out what you're doing wrong, you'll need to tell us what you're doing. Please reply with your steps and reasoning. Thank you!