probability and statistics.
posted by penny lane on .
I am preparing for a chapter test in my prob/stat class and since my teacher no longer cares about our class and the textbook is as confusing as a foriegn languaga, i am in need of help. i am trying to review an old quiz ao here is one of the questions.
the probability that a costomer selects 1,2,3,4 or 5 items at a convenience store are 3.02,.012,.023,.018 and.015, respectively.
find P(X>3.5)
find P(X<5)

I think there's a mistake with the probabilities were given. 1) probabilities can't be >1 (you get greater than 100% chance). 2) the probabilities don't add up to 1
here is what I think they should be:
.32, .12, .23, .18, .15
P(x>3.5) = probability that a customer selects more than 3.5 items = p(4) + p(5) = .18 + .15
you can do the other one by yourself. 
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