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sassytonigirl

Member

Registered: 2016-01-24

Posts: 49

Elementary statistics set 1

1. 
Express the confidence interval (0.086, 0.132) in the form of
     p−E <p <p+E.

________<p<________(Type integers or decimals).

2. 
In the week before and the week after a holiday, there were 10,000 total deaths, and 4963 of them occurred in the week before the holiday.
a. Construct a 90% confidence interval estimate of the proportion of deaths in the week before the holiday to the total deaths in the week before and the week after the holiday.
b. Based on the result, does there appear to be any indication that people can temporarily postpone their death to survive the holiday?

a. _______<p<__________(Round to three decimal places as needed.)
b. Based on the result, does there appear to be any indication that people can temporarily postpone their death to survive the holiday? (no or yes)

          No, because the proportion could easily equal 0.5. The interval is not less than 0.5 the week before the holiday.

          Yes, because the proportion could not easily equal 0.5. The interval isis substantially less than 0.5 the week before the holiday.

3.
An online site presented this question, 'Would the recent norovirus outbreak deter you from taking a cruise?' Among the 34,932 people who responded, 68% answered 'yes'. Use the sample data to construct a 95% confidence interval estimate for the proportion of the population of all people who would respond 'yes' to that question. Does the confidence interval provide a good estimate of the population proportion?   

_______< p <_______(Round to three decimal places as needed.)

Does the confidence interval provide a good estimate of the population proportion?

A.No, the sample is a voluntary sample and might not be representative of the population.
B.No, the responses are not independent.
C.Yes, the sample is large enough to provide a good estimate of the population proportion.
D.Yes, all the assumptions for a confidence interval are satisfied.

4.

Do one of the following, as appropriate. (a) Find the critical value  z α/2, (b) find the critical value t α/2, (c) state that neither the normal nor the t distribution applies.
Confidence level 95%; n=23; σ is known; population appears to be very skewed.

A.  z α/2 =1.645
B.  z α/2 =1.96
C.  t α/2 =1.717
D.  t α/2 =2.074
E.  Neither normal nor t distribution applies.

5.

A data set includes 103 body temperatures of healthy adult humans for which x = 98.1degrees°F and s=0.56°F. Complete parts (a) and (b) below.

a. What is the best point estimate of the mean body temperature of all healthy humans?
The best point estimate is ________degrees°F. (Type an integer or a decimal.)

b. Using the sample statistics, construct a 99% confidence interval estimate of the mean body temperature of all healthy humans. Do the confidence interval limits contain 98.6°F? What does the sample suggest about the use of 98.6 °F as the mean body temperature?

What is the confidence interval estimate of the population mean μ?
_______°F < μ < ________°F  (Round to three decimal places as needed.)

Do the confidence interval limits contain 98.6 °F?  (no or yes)

________No

________Yes

What does this suggest about the use of 98.6 °F as the mean body temperature?

A.This suggests that the mean body temperature could be higher than 98.6 °F.
B.This suggests that the mean body temperature could be lower than 98.6 °F.
C.This suggests that the mean body temperature could be very possibly be 98.6 °F.

Relentless

Member

Registered: 2015-12-15

Posts: 631

Re: Elementary statistics set 1

Hello!

1. E is the difference between the values and the mean, or in other words it is the half the difference between the two. P is just the mean.
I get 0.109-0.023 < p < 0.109+0.023

sassytonigirl

Member

Registered: 2016-01-24

Posts: 49

Re: Elementary statistics set 1

For this one I got 0.086 <p< 0.132

Wonder what I did wrong?

IM A DING BAT....I DIDNT GET IT WRONG...I GOT THE CORRECT ANSWER....

Last edited by sassytonigirl (2016-02-07 16:01:25)

sassytonigirl

Member

Registered: 2016-01-24

Posts: 49

Re: Elementary statistics set 1

#2
      a.   0.488 <p< 0.505
      b.   NO, because the proportion could easily....

#4
E - Neither normal nor t distribution apples

I still haven't been able to figure out number 3 and 5.  ---and #9 on a different post...

ANY help is greatly appreciated...

Thanks

sassytonigirl

Member

Registered: 2016-01-24

Posts: 49

Re: Elementary statistics set 1

PLEASE help me with 3 and 5. 

for #3 I have 0.675 <p< 0.685 but I don't know the last part of it..The word problem.  I am assuming that it is A. no, the sample is a voluntary sample and might not be representative of the population.

#5 I have done none of...

Thanks again!

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Elementary statistics set 1

For #3 I would pick A. Since the sample is voluntary it may not be a random sample of people.

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In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.