If you want the diagonal, d, to be at least 41.5 inches, what would be a possible length, width, and height for the box?

20 in, 20 in, and 27 in
21 in, 24 in, and 26 in
23 in, 24 in, and 25 in
20 in, 21 in, and 26 in

1 answer

To find the diagonal \( d \) of a box, we use the formula derived from the Pythagorean theorem in three dimensions:

\[ d = \sqrt{l^2 + w^2 + h^2} \]

where \( l \) is the length, \( w \) is the width, and \( h \) is the height of the box.

We need to determine which of the provided box dimensions results in a diagonal of at least 41.5 inches. Let's calculate the diagonal for each set of dimensions:

  1. Dimensions: 20 in, 20 in, and 27 in \[ d = \sqrt{20^2 + 20^2 + 27^2} = \sqrt{400 + 400 + 729} = \sqrt{1529} \approx 39.1 \text{ in} \]

  2. Dimensions: 21 in, 24 in, and 26 in \[ d = \sqrt{21^2 + 24^2 + 26^2} = \sqrt{441 + 576 + 676} = \sqrt{1693} \approx 41.2 \text{ in} \]

  3. Dimensions: 23 in, 24 in, and 25 in \[ d = \sqrt{23^2 + 24^2 + 25^2} = \sqrt{529 + 576 + 625} = \sqrt{1730} \approx 41.6 \text{ in} \]

  4. Dimensions: 20 in, 21 in, and 26 in \[ d = \sqrt{20^2 + 21^2 + 26^2} = \sqrt{400 + 441 + 676} = \sqrt{1517} \approx 38.0 \text{ in} \]

Now we can summarize the results:

  • Diagonal of 20, 20, and 27 in is approximately 39.1 in.
  • Diagonal of 21, 24, and 26 in is approximately 41.2 in.
  • Diagonal of 23, 24, and 25 in is approximately 41.6 in.
  • Diagonal of 20, 21, and 26 in is approximately 38.0 in.

Among these, the dimensions 23 in, 24 in, and 25 in yield a diagonal of approximately 41.6 inches, which is greater than 41.5 inches.

Thus, a possible length, width, and height for the box that meets the condition is: 23 in, 24 in, and 25 in.