Day Care Tuition A random sample of 50 four-year-olds attending day care centers provided a yearly tuition average of $3987 and the population standard deviation of $630. Find the 90% confidence interval of the true mean. If a day care center were starting up and wanted to keep tuition low, what would be a reasonable amount to charge

We have to find the 90% confidence interval for the mean

                 Given sample size  

                        Sample mean  

Population standard deviation  

Here the confidence level is 90% then  

                                                  And  

The 90% confidence interval is  

Here  is the critical value at 0.05

From the tables  

Now the 90% confidence interval is =

                                                                                     =

                                                                                     =(3840.44, 4133.56)

Hence the 90% confidence interval for the mean is (3840.44, 4133.56)

set each factor equal to 0

4x-3 = 0

2x-1 = 0

solve for x.

4x-3=0

4x=3

x= 3/4

solve for x. 

2x-1= 0

2x= 1

x= 1/2

your answer should be 1/2 is less than or equal to x and 3/4 is greater than or equal to x