Hi I really need someone's help I've been struggling with this question for what seems like forever:
Celina is buying fabric scraps to make koozies for her glasses. Each glass is cylindrical with a diameter of 4 inches and a height of 8 inches. The koozies will cover only the sides of the glasses. What is the amount of fabric she will use? What does this amount represent? Use for . Show your work.

Question

Hi I really need someone's help I've been struggling with this question for what seems like forever:
 Celina is buying fabric scraps to make koozies for her glasses. Each glass is cylindrical with a diameter of 4 inches and a height of 8 inches. The koozies will cover only the sides of the glasses. What is the amount of fabric she will use? What does this amount represent? Use  for . Show your work.

mathstudent55 · Answer

Each glass is shaped like a cylinder.
You need to find the lateral area of a cylinder, and multiply it by the number of glasses.
The lateral surface of a cylinder is shaped like a rectangle that has the circumference of the base as one side and the height of the cylinder as the other side.

mathstudent55 · Answer

Think of a cylindrical can with a label all around it. If you cut the labal vertically, along the height of the cylinder, and you unwind it and flatten it, you'll have a rectangle that has C (the circumference of the base) and h (the height of the cylinder) as its length and width.
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anonymous · Answer

could you explain further?

mathstudent55 · Answer

Your problem states to use [blank] for [blank].
I assume it is asking you to use something for pi, but you have blanks instead.
I am using 3.14 for pi.

The area of the side of each glass is
C * h = (pi)d * h = (3.14)(4 in.)(8 in.) = 100.48 in.^2
The area of each koozie is 100.48 in.^2
This amount represents the lateral area of each glass. In other words, it's the surface area of a cylinder leaving out the top and bottom bases.