Math

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I'm really stuck on these STATS questions.Can someone please help!

1. The probability of a car in a population having faulty brakes is .05. If we take a sample of 150 cars, find the standard deviation of the sampling distribution.

2. The strength of ten I-beams produced in a steel mill is an example of a..?

I think it is STATISTIC but I am not sure.
The choices are parameter, statistic, sample, population

3. What can be used in selecting samples and dividing these samples into different treatments?
a. block design
b. random number generators
c. convenience sampling
d. group design

Thankss!

  • Math -

    1. A good estimate for the mean is .05*150=7.5
    BEcause this is a Poisson Distribution, standard deviation=sqr 7.5

    2. makes no sense to me.

    3.I would go with answer b.

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