Asimple random sample of 90 is drawn from a normally distributed population, and the mean is found to be 138, with a standard deviation of 34. what is the 90% confidence interval for the population mean? use the table below to you answer the question.

The critical values for a 90% confidence interval are approximately , so the confidence interval in this case is roughly

Remember, you can do anything to an equation as long as you do it to both sidesminus 36 from both sides4.5(8-x)=66-2.5(3x+24)distribute36-4.5x=66-7.5x-60add like terms36-4.5x=-7.5x+6add 7.5x to both sides36+3x=6minus 36 from both sides3x=-30divide both sides by 3x=-10