In the year 2000, the average salaries of elementary school teachers in Oregon, Washington and Alaska were (in thousands USD) 40.9, 41.1 and Given that there were 19.7, 28.1 and 5.3 thousand teachers in these states. Find the average salary of all the elementary school teachers in the three states.

A wholesaler sold 575, 410 and 520 microwave ovens at prices (in USD) 75, 125 and 100 respectively. What is the mean price of the ovens sold?

If somebody invests TL 1,000 at 7%, TL 3,000 at 7.5% and TL 16,000 at 8%. What is the overall percentage yield of these investments?

The number of employees of the municipalities in a certain area of a country were given in the following table Find the mean and modal class? #Frequency

THE MODE - If a data set has only one value that occurs with greatest frequency is said to be UNIMODAL -If a data set has two values that occur with the same greatest frequency is said to be BIMODAL -If a data set has more than two values that occur with the same greatest frequency, each value is used as the mode, and the data set is said to be MULTIMODAL -When no data value occurs more than once, the data set is said to have NO MODE

Example: The following data represent the duration (in days) of Space Shuttle voyages for the years (18 values) 8,9,9,14,8,8,10,7,6,9,7,8,10,14,11,8,14,11 Q: Find The Mode

Example: A manager of clothing store wants to approximate the median age of both his male and female customers so that he can take this into account when ordering stock. The following data are obtained (age in years) Female (x)Male (y) Q: Find the median age in years for both female and male customers

Example: These data are obtained on the sales per day in thousand of TRL at two franchises of the same hamburger chain. 0,92,51,42,6 1,73,23,61,3 2,93,82,75,9 3,50,74,84,7 Franchise AFranchise B 0,90,74,50,6 0,94,60,35,3 1,43,15,24,2 2,55,11,75,0 A- Find the sample mean for each franchise. Based on statistics, does it appear that the average sales per day for A is about the same as that for B? Explain. B- Find the sample median for each franchise. Based on statistics, does it appear that the average sales per day for A is about the same as that for B? Explain. C- Is it safe to say the distribution of sales per day is the same for these two franchises?.

MONTHLY STARTING SALARY (In TRL) GraduateMonthly Starting Salary 12,850 22,950 33,050 42,880 52,755 62,710 72,890 83,130 92, , , ,880 TOTAL: 35,280

Properties of the Mean 1- The Mean can be calculated for any set of NUMERICAL Data 2- The Mean is unique and unambiguous value. 3- The means of several sets of data can always be combined into the overall mean of all the data. 4- If each value in a sample were replaced by the mean, then ∑X would remain unchanged 5- The mean takes into account the value of each item in a set of data. 6- The mean is relatively reliable in the sense that means of many samples drawn from the same population generally do not fluctuate, or vary, as widely as other statistics used to estimate the mean of a population.

Properties of the Median In addition to the properties of the Mean; 1- It splits the data into two parts 2- The median is preferable to the mean because it is not so easily affected by extreme values.

Problem: The following list gives the duration in minutes of 24 power failures Find the median.

Data Set: Apartment Rents (in ascending order) Data Set: Apartment Rents

Standardized Values for Apartment Rents

Monthly Starting Salaries for a sample of 12 business school graduates Graduat e Monthly Starting Salary (TRL) 12,020 22,075 32,125 42,040 51,980 61,955 72,050 82,165 92, , , ,040

A testing lab wishes to test two experimental brands of outdoor paint to see how long each will last before fading. Two groups from different agents are formed with 6 cans of each. The results (in Months) are shown: Brand ABrand B

A student scored 65 on statistics test that had a mean of 50 and a standard deviation of 10, she scored 30 on history test with a mean of 25 and a standard deviation of 5. Compare her relative positions on the two tests

App.GradeApp.GradeApp.GradeApp.Grade Table: Ordered Array of Aptitude Test Scores for 40 Job Applicants. ∑x=2338 and ∑x 2 =157262