Question

#7 can someone explain or is it in the Zchart?

t information is necessary to calculate t ts better? Wh 2. What 2 What interval? ate a conde at is the margin of error? ant by the 95% confidence interval of Vhat are three properties of a good estimat 6. What statistic best estimates p 7. Find each. /2 for the 99% confidence interval b. Zan for the 98% confidence interval C. Za/2 for the 95% confidence interval d. Za/2 for the 90% confidence interval za/2 for the 94% confidence interval 8. What is necessary to determine the sample size? 9. Fuei Efficiency of Cars and Trucks Since 1975 the av- erage fuel efficiency of U.S. cars and light trucks (SUVs) has increased from 13.5 to 25.8 mpg, an increase of over 90% ! A random sample of 40 cars from a large commu- nity got a mean mileage of 28.1 mpg per vehicle. The pop ulation standard deviation is 4.7 mpg. Estimate the true mean gas mileage with 95% confidence. Source: World Almanac 2012 hru Customers A rande of 50 cars in the drive-thru of a popular fast fo ntion is $5.92. Estimate 10. Fast-Food Bills for Drive- nyealed an average bill of $18.21 per ca 98% с

Answer 1