Question

what is the formula to calculate the longest length which can be fit in a cuboid?

Answer 1

$longest \: length \: = \sqrt{ {l}^{2} + ({b}^{2} + {h}^{2})$

Answer 2

I think it can be measured by the formula of finding diameter of cuboid ..
which is square root of (L^2 + B^2 + H^2)
here L is the length of cuboid
B is the breadth of cubiod
& H is the height of cubiod...