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)

i dont know sorry

step-by-step explanation:

the final amount you will pay is $68.04.

the tip is determined by the pre-tax amount, so we calculate the tip based on the original bill, not after we've added sales tax.

to find the tip:

we can divide 54.00 by 100 to get 1% of 54. then we multiply that by 18.

54 / 100 = .54

.54 x 18 = 9.72

tip = 9.72$

to find the tax:

we can divide 54.00 by 100 to get 1% of 54. then we can multiply that by 8 to get 8%.

54 / 100 = .54

.54 x 8 = 4.32

tax= 4.32

now we can add the tip and tax to the bill to get our total.

54 + 9.72 + 4.32 = 68.04

total: $68.04

step-by-step explanation: