Activities

1. Find the perimeter of the rectangle.
   

2. Find the area of the rectangle

3. The perimeter of the rectangle below is 24 m.  What is the measure of the missing side length?  Show your work.
   

   

4. Compare the area of a square that has a side length of 6 mm and the area of a rectangle that has a length of 5 mm and a width of 7 mm.  Show your work.

5. The rectangle below has an area of 48 units².  What would the perimeter of the rectangle be? Show all your work.

6. Draw 3 different rectangles that have a perimeter of 20 ft.

7. Sandy is buying dirt to fill in her garden so she can plant some vegetables.  The shape of the garden is shown below. How much dirt will she need to buy?  If the dirt comes in bags that cover 4 square feet, how many bags will she need to buy? Show all your work.

8. A picture is placed in the frame below.  If you want to buy wood to make another frame that is the same size and shape, how much wood do you need to buy? Show all your work.

Answer Key/Rubric

1. 20 cm

2. 60 in²

3. The missing side is 7 m.
   Student work might include, but is not limited to:

• Find total given: 5 + 5 = 10
• Find missing amount: 24 – 10 = 14
• Split missing amount up between the two equal sides: 14 ÷ 2 = 7
• Check: 5 + 5 + 7 + 7 = 24

4. The area of the square is greater than the area of the rectangle.
   Student work might include, but is not limited to:

• Area of square:

• Area of rectangle:

• 36 > 35

5. The perimeter of the rectangle is 28 units.
   Student work might include, but is not limited to:

• Find the missing side length by dividing the area by the one given side length:  48 ÷ 6 = 8
• Find the perimeter:  6 + 8 + 6 + 8 = 28

6. Possible rectangles that can be drawn are listed by dimensions in the table below: 

• Students can also reverse the lengths and widths that are given in the table. 
• Rectangle sides that are drawn should be close to the dimensions that the student chooses.  For example a 1 by 9 rectangle should not look like a square.
• A 5 by 5 square is acceptable for this problem because a square has all the properties that a rectangle has.

7. Sandy needs a total of 76 ft² of dirt.  That means that she will need to buy 19 bags to cover the entire garden.
   Student work might include, but is not limited to:

• Decompose the garden into two rectangles and find the area of each one.

• Rectangle A:

• Length is 8 ft. but the width is missing. 
• Add the measurements of the two shorter vertical sides, to find the total length of the longer vertical side:  2 + 4 = 6 ft.
• Area: 6 x 8 = 48 ft²

• Rectangle B:

• Width is 4 ft. but the length is missing.
• Subtract the total length of the shape minus the length of A to get the length of B: 15 – 8 = 7 ft.
• Area = 7 x 4 = 28 ft²
• Add the areas together to find the total area of the garden: 48 + 28 = 76 ft²
• To find the number of bags that Sandy will use divide the total needed by the amount each bag contains:  76 ÷ 4 = 19 bags

8. You would need to buy 36 in² of wood to make the same picture frame.
   Student work might include, but is not limited to:

• Find the area of the outside rectangle: 12 x 8 = 96 in²
• Find the area of the inside rectangle (the picture): 6 x 10 = 60 in²
• Subtract the area of the picture from the area of the larger rectangle to find the amount that is left to make the picture frame:  96 – 60 = 36 in²