Math Challenge

Write your answers in the box. Print the page and place it in your folder or portfolio.

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Go to and read the instructions on how to find the cubic feet or square feet of an area. When you finish, click the BACK button on your browser to return to this page.

Notice that the dimension of the microwave ovens you compared was 1.6 cu. ft. The abbreviation for cubic is "cu." and for feet is "ft."

Suppose you want a very large microwave to fit a small turkey. You need the unit to be at least 1.5 ft high, 2 ft deep, and 2 ft wide. How many cubic feet would you have?

Following are some questions posed by people on the Internet. Can you answer them?

I need to build a coal bin that will hold 40 cubic feet. How do I figure out what size box I need to build?

Funny Answer: Wouldn't it be a whole lot simpler just to call up the coal company, order 40 cubic feet of coal, have it dumped on your lawn or in your driveway (or maybe the parking lot for your apartment building) get a whole bunch of lumber and plywood and nails and a hammer and saw, and just make a box big enough to put all the coal into? If it's not big enough to hold all the coal, then you add on a little bit more vertically, and if the box is too big, then you take most of the coal out, cut the box down, and make it fit. Sheesh - the idea of using complicated math when you can do it so easily by hand.

Serious Answer: If you build it as a "rectangular solid" (the most reasonable shape) with length (l), width (w), and height (h), then the volume is given by l*w*h (the sign * = times or X). In your case, you want l*w*h= 40 cubic feet.  [So select a size to the length and width and what's left will be the height.] If the length is 3 feet and the the width 3 feet, how high would it have to be?]

I have a box that is 13 x 24 x 15.5. How do I figure out the cubic feet it holds?