Three screw problem

Question

There are three identical screws with diffrent amounts of nuts and disks on them.

Here is the problem picture:

How do you calculate the weight of a screw, the nuts and the disks?

Answer 1

Considering the three images, we can say

\begin{cases} 1B+3D+1H &=55\\ 1B+1D+2H &=42\\ 1B+2D+3H &=56 \end{cases}

Where $B$ stands for the weight of bold, $D$ the disk's and $H$ the hexagon piece. Solving the system, we have \begin{cases} B &=23,\\ D &=9,\\ H &=5. \end{cases}