# complete middle grade mathematics discussion |cheapassignmenttutors.com

complete middle grade mathematics discussion | cheapassignmenttutors.com

THIS DISCUSSION HAS 3 PARTS:

__Discussion Post_July 2__:

__Activity 1__: Surface Area Formulas

- Choose one cylinder and itâ€™s corresponding cone (same base and height)
- Use the Nets to come up with a formula for the surface area of these two 3D shapes. (FYI: the â€œnetâ€ of a 3D shape is when it is opened and unfolded to create a flat shape. The flat shape is called a â€œnetâ€. The â€œnetâ€ is what I provided for you on June 27)
- Can you generalize these formulas for any cylinder? And any cone?

**For the discussion post,** write your derived formula for the surface area of a cylinder and a cone. How did you find this?

__Activity 2:__ Surface Area Video

- Watch the video titled â€œSurface Area of Cylinders.â€
- In this video, students are discussing the surface area of a cylinder.

**For the discussion post, **answer the following questions:

- What teacher moves helped the students in the video generate the formula for the surface area of a circle-based cylinder?
- How would you want to respond to the studentâ€™s last question in the video?

__Activity 3:__ Surface Area of a Sphere (â€œOrangeâ€ You Glad?)

You are going to use an orange to investigate the surface area of a sphere.Before you begin, make sure you know the definition of surface area, radius, and circumference.

Materials:

- Orange
- Knife
- Paper plate

Instructions

- Squeeze and roll one orange around making it as spherical as possible.
- Cut the orange into two equal halves (hemispheres) to reveal a great circle of the orange.
- Lay the orange face down on a paper plate and trace it.
**PREDICT**how many great circles can be covered with the pieces of your orange peel.___________- Trace several more great circles onto the plate.
- Tear off pieces of the orange peel, each about 1 square inch (or slightly smaller) in size.
- Place pieces in one of the circles. Fill the circle as much as possible without overlapping the pieces.
- Continue filling circles until you are out of orange peel.

Use your results to answer the following questions in complete sentences.

- Write a (general) mathematical expression that tells the amount of area you covered on a single circle.Be sure to define your variables.______________________________
- How many circles did you cover in all? ______ Based on this result, write a mathematical expression that tells the surface area of your orange (sphere). _________________

**For the discussion post,** write your derived formula for the surface area of a sphere. How did you find this?