We know that 6 concrete broks weigh 90 kilograms so we can fin hoy much weigh each brok like this:
![(90)/(6)=15](https://img.qammunity.org/2023/formulas/mathematics/high-school/aloicf2hft06jh77lobaacfd789mmvntbt.png)
Now we can complete the table with this factor so:
![\begin{gathered} 1\to15 \\ 2\to30 \\ 3\to45 \\ 4\to60 \\ 5\to75 \\ 6\to90 \\ 7\to105 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/znc4kdmgzo36n03j7axity7qk4ef4gns7z.png)
the constant of proportionality will be:
![k=(y)/(x)=(105)/(7)=15](https://img.qammunity.org/2023/formulas/mathematics/college/kz734de1l3pmkxiby6amlev5ebdhfhsn51.png)
And the number next to the one will be 15 and that means that 1 brick weigh 15 kilograms