MHB Binomial Experiments: Find Probability of x=5, x>=6, x<4

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The discussion centers on calculating probabilities for a binomial experiment involving U.S. adults' trust in national newspapers. The correct values for the experiment are n=9, p=0.6, and q=0.4, with x representing the number of adults who trust the newspapers. The user initially confused the probability p with 0.63 but confirmed it should be 0.6 based on the problem statement. Calculations for the probabilities of exactly five, at least six, and less than four trusting adults can be done using the binomial probability formula or calculator functions. The user ultimately resolved their confusion regarding the values and methods needed for the calculations.
aprilryan
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Hi all,

I'm a bit confused on this problem in my book.

"Specify the values of n, p, and q and list the possible values of the random variable x.
Sixty percent of U.S. adults trust national newspapers to present the news fairly and accurately. You randomly select nine U.S. adults. Find the probability that the number of U.S. adults who trust national newspapers to present the news fairly and accurately is (a) exactly five, (b) at least six, and (c) less than four."

I have the values.

n=9
p=.63
q=.37
x=5
x is at least six
x<4

Would I have to do them on the calculator using binomial pdf and sum commands or find the mean, standard deviation and variance?

Note: I have been shown to do these types of problems on the calculator using the binomial pdf and sum commands.
 
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aprilryan said:
Hi all,

I'm a bit confused on this problem in my book.

"Specify the values of n, p, and q and list the possible values of the random variable x.
Sixty percent of U.S. adults trust national newspapers to present the news fairly and accurately. You randomly select nine U.S. adults. Find the probability that the number of U.S. adults who trust national newspapers to present the news fairly and accurately is (a) exactly five, (b) at least six, and (c) less than four."

I have the values.

n=9
p=.63
q=.37
x=5
x is at least six
x<4

Would I have to do them on the calculator using binomial pdf and sum commands or find the mean, standard deviation and variance?

Note: I have been shown to do these types of problems on the calculator using the binomial pdf and sum commands.

Where does $p = 0.63$ comes from? I would say it should be $p=0.6$ according to the question.
 
Yes, it was .60. Thanks, I've got this one figured out!
 
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