ch 6 ex24: In a survey of2255

randomly selected US adults (age18

or older),1787 of them use the Internet regularly. Of the Internet users,1054

use a social networking site.¹Find a99%

confidence interval for each of the following proportions. (a) Proportion of US adults who use the Internet regularly.

Round your answers to three decimal places.

The99%confidence interval is( ?)to (? )

Ch 6 ex46: Use the normal distribution and the given sample results to complete the test of the given hypotheses. Assume the results come from a random sample and use a5%

significance level.

TestH0:p=0.5

vsHa:p>0.5

using the sample resultsp^=0.56

withn=75

Round your answer for the test statistic to two decimal places, and your answer for thep-value to three decimal places.

test statistic =Enter your answer; test statistic?

p-value =Enter your answer; p-value?

Conclusion:Choose the answer from the menu; Conclusion?

ch 6 ex180 :Use the formula to find the standard error of the distribution of differences in sample means,x1-x2

Samples of size100from Population1with mean95 and standard deviation11and samples of size80 from Population2with mean77and standard deviation17

Round your answer for the standard error to two decimal places.

standard error=?

Enter your answer in accordance to the question statement

ch6 ex206 :Use thet-distribution and the given sample results to complete the test of the given hypotheses. Assume the results come from random samples, and if the sample sizes are small, assume the underlying distributions are relatively normal.

TestH0:1=2

vsHa:1>2

using the sample resultsx1=56,s1=8.2withn1=30andx2=51,s2=6.9withn2=40

(a) Give the test statistic and thep-value?

Round your answer for the test statistic to two decimal places and your answer for thep

-value to three decimal places.

test statistic=?

p-value=?

ch6 ex210: Use thet-distribution and the given sample results to complete the test of the given hypotheses. Assume the results come from random samples, and if the sample sizes are small, assume the underlying distributions are relatively normal.TestH0:1=2vsHa:12

using the sample resultsx1=15.3,s1=11.6withn1=100andx2=18.4,s2=14.3withn2=80

(a) Give the test statistic and thep-value.?

Round your answer for the test statistic to two decimal places and your answer for thep-value to three decimal places.

test statistic =?

p-value =?