Problem:
You need to make an open-top box from a rectangle of cardboard 9 by 13 inches by cutting a square from each corner and folding up the sides. You want the box to have the maximum possible volume. Complete the following problems showing all your work:
If each square you cut out is x by x inches, write an expression for the volume of the box, V(x), in terms of x. A sketch may help. Show all your work.
Sketch (or use technology to plot) the function to find the maximum. Clearly label or state the (x,y) coordinates of the value of x that optimizes the function and the maximum Volume (y)
How many dollars worth of quarters (25 cent pieces) would it take to fill the box? Show all your work!
You need to make an open-top box from a rectangle of cardboard 9 by 13 inches by cutting a square from each corner and folding up the sides. You want the box to have the maximum possible volume. Complete the following problems showing all your work:
Unfortunately, I do not know the diameter and height of a 25-cent pieces!
A quarter has a diameter of 24.26 mm ≈ .955 in
And the height (thickness) is 1.75 mm ≈ .0689 in
So....the volnme of one quarter is the volume of a cylinder with a diameter of 955 in and a height of .0689 in =
pi ( .955/2)^2 * ( .0689) ≈ .04935 in^3
So (theoretically), the number of quarters that would fit in the box is ≈ 182.876 in^3 / .04935 in^3 ≈ 3706 quarters