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Probability

mathjunkie1990

New member
Joined
Nov 14, 2009
Messages
7
ok so i am messing up somewhere and i have gone thru all the steps.
mine says 20% wont show up which means 80% will. 310 people were invited and the max is 273.

Mean=310*.8=248
Variance=310*.8*.2=49.6
Stand. dev.=sqr.rt. of 49.6=7.04

(310-248)/7.04=8.807
that does not fit in the standard normal model.
can you please help?
 

tkhunny

Moderator
Staff member
Joined
Apr 12, 2005
Messages
9,706
Please review the Domain of the Standard Normal Distribution.

When you REALLY get it, tell me again that 8 "does not fit".
 
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