The following data represents the age (in weeks) at which babies first crawl based on a survey of 12 mothers conducting by Essential Baby:

52 30 44 35 47 37 56 26 39 26 39 28

a. FInd the mean of the sample

b. FInd the standard deviation of the sample

c. Construct a 95 percent confidence interval estimate for the mean age at which a baby first crawls. ( Assume the data comes from a National distribution.)

6. The following data represnts the asking price of a simpe random sample of homes for sale in Lexington, Kentucky, in June 2005:

227,900 143,000 459,900 299,900 205,800 147,800

239,900 219,900 159,900 187,500 264,900 279,900

a. Determine which number is the outlier. Be sure to confirm it!

b. Construct a 99% confidence interval with the outlier included.

c. Construct a 99% confidence interval with the outlier removed.

d. What effect does an outlier have onthe confidence interval?

Outliers=1.5 (Q3-Q1) You can use your calculator to find the Q1 and Q3. Or, you can arrange the in order and selct the medin, Q1 and Q3.