Question

 (36) Estimators are used in two different ways: point estimation and confidence estimation.

 (1) True.

 (2) False.

 (37) Which of the statements about large-sample estimation is correct?

 (1) An estimator should be unbiased and the spread (as measured by the mean) should be as small as possible.

 (2) The distance between an estimate and the true value of the statistic is called the error of estimation.

 (3) The 95% Margin of error is: 1.96 x Standard error of the estimator.

 (4) A good confidence interval is as wide as possible.

 Problem H: A study has been undertaken related to Highschool Students and Information

 Technology. A random sample of 250 students showed that 85 of them owned a laptop.

 (38) Refer to Problem H. Estimate the proportion of all students who own a laptop.

 (1) 0.034

 (3) 0.34

 (2) 0.5

 (4) 0.85

 (39) Refer to Problem H. Calculate the 95% margin of error for your estimate.

 (1) 0.049

 (3) 0.070

 (2) 0.059

 (4) 0.073

(40) Refer to Problem H. Calculate a 90% confidence interval for the population proportion p

 of students who own a laptop.

 (1) 0.34 ± 0.049

 (3) 0.34 ± 0.059

 (2) 85 ± 0.0049

 (4) 85 ± 0.059

Answer 1

Ans 36 ) True

Ans 37) option 3 is correct because z at 95% is 1.96

and margin of error = 1.96* standard error

using excel>addin>phstat>confidence interval

we have

Confidence Interval Estimate for the Proportion
Data
Sample Size	250
Number of Successes	85
Confidence Level	90%
Intermediate Calculations
Sample Proportion	0.34
Z Value	-1.6449
Standard Error of the Proportion	0.0300
Interval Half Width	0.0493
Confidence Interval
Interval Lower Limit	0.2907
Interval Upper Limit	0.3893

Ans 38) option 3 is true

Ans 39) option 2 is true

Ans 40 ) option 1 is true