Questions 9,10,11

. your company wants to improve sales, Past sales data indicate that the average sale was $1 10 per transaction. After training your sales force, recent sales data (taken from a sample of 25 sall en) indicates an average sale of $127, with a standard deviation of $15. Did the training work? Test your hypothesis at a 5% level of significance. a. Write Null and alternate hypothe b. Find Sample Test Statistics (write formula and round your answer to two decimal places) c. Find P.value and compare with a (round your answer to four decimal places) d. Do you reject or fail to reject Ho e. Write a good conclusion in the context of the application f. Find a confident interval (use a from the problem) g. Write the possible error 10. If you want to test a car manufacturer's claim that their cars give a highway mileage of more than 21 km on an average, You sample 11 cars from the dealership have highway mileages 20, 22, 25, 24, 19, 18, 20, 19, and 21. Do we have sufficient evidence to prove that the manufacturer's claim is true at a 5% level of significance? a. Write Null and alternate hypotheses. b. Find Sample Test Statistics (write formula and round your answer to two decimal places) c. Find P-value and compare with a (round your answer to four decimal places) d. Do you reject or fail to reject Ho e. Write a good conclusion in the context of the application f. Find a confident interval (use a from the problem) g. Write the possible error 11. A researcher claims that xxx Party will win in next Senate elections especially in Florida State. A statistical data reported that 25% voted for xxx Party in last election. To test the claim a researcher surveyed 80 people and found 45 said they voted for xxx Party in last election. Is there enough evidence at a=0.05 to support this claim? a. Write Null and alternate hypotheses. b. Find Sample Test Statistics (write formula and round your answer to two decimal places) c. Find P-value and compare with a (round your answer to four decimal places) d. Do you reject or fail to reject Ho e. Write a good conclusion in the context of the application f. Find a confident interval (use a from the problem) g. Write the possible error