Posts: 1,041

Threads: 15

Joined: Jan 2005

Quote:

Thanks for your help,
I still don't understand how to get the result 0.544945 by calculator. if i try it manually (by interpolation) it is no problem. by calclator it equals .643312. do you know what i have to type in to get the right result?

Well, if I type in 0 1 .1129 [+/-] UTPN [ENTER] on any RPL

calculator, it returns .544945081834.

11.5 961 .1129 UTPN [ENTER] returns .643311996636.

My guess is that you're misinterpreting your normal distribution

table. With a variance of 961, the standard deviation is 31. The

difference between your mean and x values is 11.5-.1129=11.3871, so

your x value is 11.3871/31=.367325806452 standard deviations below

the mean, so try .3673 in your normal distribution table.

Regards,

James

*Edited: 25 July 2006, 6:59 a.m. after one or more responses were posted*