SOLUTION: I just can't figure this one out and do not understand the example in our book! A local newspaper recently conducted a survey of 400 households in the community to determine the n

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Question 380361: I just can't figure this one out and do not understand the example in our book!
A local newspaper recently conducted a survey of 400 households in the community to determine the number of daily newspapers that were being delivered to the residence. Results were used to obtain the following probability distribution:
X 0 1 2 3 4 or more
P(x) 0.15 0.35 0.35 0.10 0.05
What is the probability that a household receives at most 2 daily papers?
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
The key word "At most 2 newspapers" means X<=2

P(X<=2) = P(X=0) + P(X=1) + P(X=2)

P(X<=2) = 0.15 + 0.35 + 0.35

P(X<=2) = 0.85


So the probability that a household receives at most 2 daily papers is 0.85 (ie an 85% chance)