Todays TnT Tip

Using Spreadsheets to Calculate Perimeter and Area of Rectangles

For this activity cut construction paper into rectangles of varying sizes. Provide the students with a ruler and a worksheet that has the following lines for each shape:

Shape 1: Length_________Width__________
Perimeter_____________ Area____________

Have the students measure the rectangles and write the measurements on the worksheet. If you want to make this a self-checking activity, have the students calculate the perimeter and area before putting the information in the spreadsheet.

To set up the spreadsheet for self-checking use the following format:

In cell A1 type Length
In cell B1 type Width
In cell C1 type Perimeter
In cell D1 type Area
In cell C2 type the following formula - =sum((2*a2)+(2*b2))
Press the Enter key
Click back in cell C2 and highlight enough cells under that cell to equal the number of shapes measured
Click Edit--Fill--Down
In cell D2 type the following formula =sum(a2*b2)
Press the Enter key
Click back in cell D2 and highlight the same number of cells in that column as you did in column C
Click Edit--Fill--Down
Save your spreadsheet.

It is now ready for students to use to either calculate the perimeter and area or to check their work.

Happy computing!