Mean:

                      -- Also known as the average.  The mean is found by adding up all of the given data and
             dividing by the number of data entries.

                Example:
                             - the grade 10 math class recently had a mathematics test and the grades were as
                               follows:
 

                                       78
                                       66
                                       82                                  464 / 6 = 77.3
                                       89
                                       75                        Hence, 77.3 is the mean average of the class.
                                    + 74
                                      464

     Median:

                      -- The median is the middle number.  First you arrange the numbers in order from lowest
                to highest, then you find the middle number by crossing off the numbers until you reach the
                middle.

              Example:
                               - use the above data to find the median:

                                                66  74  75  78  82  89\

                            - as you can see we have two numbers, there is no middle number.  What do we do?
                   It is simple; we take the two middle numbers and find the average, ( or mean ).

                                                             75 + 78 = 153

                                                              153 / 2 = 76.5

                             Hence, the middle number is 76.5.
 

         Mode:

                        -- this is the number that occurs most often.

                 Example:
                                 - find the mode of the following data:
 

                                    78  56  68  92  84  76  74  56  68  66  78  72  66
                                    65  53  61  62  78  84  61  90  87  77  62  88  81

                                                   The mode is  78.

Software:  Microsoft Excel

Goal:  To Create a computerized version of a worksheet showing projected expenses for a University students' fall term.  The design of the worksheet is based on this hand-drawn planning version.

1)     The first step is to launch MS Excel or Open Office Calc and start a new worksheet.

2)     Next, type descriptive labels for the worksheet and TITLE, and label the rows and columns.  You may have to adjust the column widths in order to accommodate some of the longer and shorter headings.

3)     You should now also try to change the format of the cells to allow them to show the dollar sign figures (currency).  Try using the shortcut method (right click) when you have the desired cells selected.

4)     Now the data:

a)     Tuition and fees were a one-time fee which you paid in September ($1450)

b)    Books were also a one-time fee, also paid in September. ($450)

c)     Rent is a constant $250 a month, however you had to pay a $125 dollar damage deposit in your first month.

d)    Utilities are getting more expensive as the cold sets in. (Sept. $50, Oct. $60, Nov. $75, Dec. $95)

e)     Food is a constant $160 a month.

f)      Transportation is also a constant $120 a month.

g)     Odds and ends have been $100 a month for the first three, however this increases in December by $300 for your Christmas shopping.

5)     Once you have the data filled in, you need to calculate the totals for each month, as well as the totals for each row.

6)     Once the formulas are entered, and totals are complete, you should format the worksheet to make it much more attractive.  Change to suit your own tastes, however, keeping in mind that the worksheet will be read by others and should be readable. 

7)     You may send the worksheet to your instructor at this point, OR you may want to try the additional activity below.

Extra Activity : Creating Charts to accompany the worksheet.

1)     Using the worksheet from the previous section, create a chart depicting the data entered in a graphical form,

Some Guidelines:

a)     Highlight the data from the worksheet from which you wish to chart.

b)    From insert, choose chart.

c)     Choose a column chart

d)    The column chart often looks best when the months lay on the horizontal axis (bottom).  To do this choose "series: in rows"

e)     The chart should be placed on the same page as your worksheet.  Make sure the two do not overlap.

f)      Save the resulting document and email to your instructor as an attachment.

When rounding whole numbers there are 2 rules to remember:

I will use the term rounding digit - which means: When asked to round to the closest tens - your rounding digit is the second number to the left (ten's place) when working with whole numbers. When asked to round to the nearest hundred - the third place from the left is the rounding digit (hundreds place).

Rule 1. Determine what your rounding digit is and look to the right side of it. If the digit is 0,1,2,3 or 4 do not change the rounding digit. All digits that are on the right hand side of the requested rounding digit will become 0

Rule 2. Determine what your rounding digit is and look to the right of it. If the digit is 5,6,7, 8 or 9, your rounding digit rounds up by one number. All digits that are on the right hand side of the requested rounding digit will become 0

Rounding with decimals: When rounding numbers involving decimals, there are 2 rules to remember:

·        Rule 1. Determine what your rounding digit is and look to the right side of it. If that digit is 4,3, 2 or 1, simply drop all digits to the right of it.

·        Rule 2. Determine what your rounding digit is and look to the right side of it. If that digit is 5, 6, 7, 8 or 9 add one to the rounding digit and drop all digits to the right of it.

·        Rule 3: Some teachers prefer this method:

This rule provides more accuracy and is sometimes referred to as the 'Banker's Rule'. When the first digit dropped is 5 and there are no digits following or the digits following are zeros, make the preceding digit even (i.e. round off to the nearest even digit). E.g., 2.315 and 2.325 are both 2.32 when rounded off to the nearest hundredth. Note: The rationale for the third rule is that approximately half of the time the number will be rounded up and the other half of the time it will be rounded down.

Examples:

765.3682 becomes:

1000 when asked to round to the nearest thousand (1000)

800 when asked to round to the nearest hundred (100)

770 when asked to round to the nearest ten (10)

765 when asked to round to the nearest one (1)

765.4 when asked to round to the nearest tenth (10th)

765.37 when asked to round to the nearest hundredth (100th.)

765.368 when asked to round to the nearest thousandth (1000th)

Job Description: A Plumber is responsible for installing, repairing and maintaining pipes, fixtures and other plumbing used for water distribution and waste water disposal in residential, commercial and industrial buildings.

Yearly Gross Income:  $75,000               ß before taxes

Tax Bracket: 35.39%      ß see Canadian tax brackets handout

Yearly Net income: $48,457.50   ß after taxes

Monthly Expenses

                                                                                                                        Total: $2220

Monthly Net Income:  $4028.13   ß yearly net income ÷ 12 months

-  Monthly Expenses  $2220

= $1808.13  leftover

Job Description: A Plumber is responsible for installing, repairing and maintaining pipes, fixtures and other plumbing used for water distribution and waste water disposal in residential, commercial and industrial buildings.

Yearly Gross Income:  $75,000               ß before taxes

Tax Bracket: 35.39%      ß see Canadian tax brackets handout

Yearly Net income: $48,457.50   ß after taxes

Monthly Expenses

                                                                                                                        Total: $2220

Monthly Net Income:  $4028.13   ß yearly net income ÷ 12 months

-  Monthly Expenses  $2220

= $1808.13  leftover