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View Full Version : Why is Z0.05 = 1.645?

hanelliot
04-25-2009, 11:56 AM
I'm using a standard normal table from back of my text, and I can't find 1.645 anywhere. If anything, shouldn't it be 0.4801? What am I missing? Please see the table I'm using for reference.. thank you

http://img340.imageshack.us/img340/8458/teste.jpg

Dragan
04-25-2009, 01:42 PM
I'm using a standard normal table from back of my text, and I can't find 1.645 anywhere. If anything, shouldn't it be 0.4801? What am I missing? Please see the table I'm using for reference.. thank you

http://img340.imageshack.us/img340/8458/teste.jpg

You’re reading the table incorrectly. The value of p=0.4801 is the proportion of under the standard normal distribution that is to the right of a Z-score of 0.05.

Use (only) the first column on the left to obtain a Z-score…i.e. go down this column and look for 1.6 – then move to right to find the second decimal place 1.64 and subsequently obtain the proportion of the curve to right of this value which is approximatley 0.05

hanelliot
04-25-2009, 02:09 PM
Thank you! :)