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Statistics Help

  1. Apr 1, 2004 #1
    I need help on the following Questions that I'm working on. Can someone explain to me and show me how they came up with the answers. Thank you.

    :confused:


    #1

    The events X and Y are mutually exclusive. Suppose P(X) = .05 and P(Y) = .02. What is the probability of either X or Y occurring? What is the probability that neither X nor Y will happen?


    #2

    If you ask three strangers on campus, what is the probability: (a) All were born on Wednesday? (b) All were born on different days of the week? (c) None were born on a Saturday?

    #3

    In a binomial situation n=5 and pie = .40 Determine the probabilities of the following events using the binomial formula.

    a. x = 1

    b. x = 2


    #4

    Steele Electronics, Inc. sells expensive brands of stereo equipment in several shopping malls throughout the northwest section of the United States. The Marketing Research Department of Steele reports that 30 percent of the customers entering the store that indicate they are browsing will, in the end, make a purchase. Let the last 20 customers who enter the store be a sample.

    a. How many of these customers would you expect to make a purchase

    b. What is the probability that exactly five of these customers make a purchase?

    c. What is the probability ten or more make a purchase?

    d. Does it seem likely at least one will make a purchase?



    #5

    A recent article in the Myrtle Beach Sun Times reported that the mean labor cost to repair a color TV is $90 with a standard deviation of $22. Monte’s TV Sales and Service completed repairs on two sets this morning. The labor cost for the first was $75 and it was $100 for the second. Compute z values for each and comment on your findings.


    #6

    The mean starting salary for college graduates in the spring of 2000 was $31,280. Assume that the distribution of starting salaries follows the normal distribution with a standard deviation of $3,300. What percent of the graduates have starting salaries:

    a. Between $30,000 and $35,0000

    b. More than $40,000

    c. Between $35,000 and $40,000
     
  2. jcsd
  3. Apr 1, 2004 #2

    matt grime

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    Science Advisor
    Homework Helper

    1. Look up the definitoins.
    2. think about it a little
    3. what's x?
    4. see 2.
    5. what's z?
    6. use the formulae even though the assumptions are ridiculous.


    sorry, but the questions that make sense are failrly easy, and this is obviously homework, and a lot more good will come if you try ther homework yourself, perhaps seying what you've done will demonstrate you've tried it at least in part.
     
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