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## Comment on

3-D Diagonal## Why did you assume that there

## We're told that we have a

We're told that we have a RECTANGULAR box. So, there are 90-degree angles at each corner.

Cheers,

Brent

## does this formula work for a

## Yes, the formula in the video

Yes, the formula in the video will work for cubes as well.

NOTE: The formula finds the straight line distance (the shortest distance) between the opposite vertices.

That is, if a fly were to DIRECTLY travel from one vertex to the opposite vertex, we can use the formula to find that distance.

The question at https://greprepclub.com/forum/tricky-each-edge-of-the-above-cube-has-len... is slightly different.

In that linked question, the ant doesn't travel the shortest distance from A to B. Instead, the ant walks from point A to point B along the OUTSIDE of the cube.

Does that help?

Cheers,

Brent