about 780
http://davidmlane.com/hyperstat/z_table.html
the battery lifetime is normally distributed for large samples with a standard deviation of 70 days. if 16% of the batteries have a lifetime of 850 or higher, what is the average battery life?
2 answers
open
http://davidmlane.com/normal.html
enter 70 into SD
click on <above> and enter 850
adjust Mean until you get .16 in the area (probability) window
I had 780.39 days as the mean.
http://davidmlane.com/normal.html
enter 70 into SD
click on <above> and enter 850
adjust Mean until you get .16 in the area (probability) window
I had 780.39 days as the mean.
1 answer