I am struggling to find a ground for this question
So I have a mercury thermometer. There's a $0.2\, \mathrm{cm^3}$ void in the glass. The question asks for the new volume of void after a change in temperature.
Below are the known quantities $$\Delta T \\ \beta_{\text{mercury}} \\ \beta_{\text{glass}}$$
Normally, if the initial volume of two materials are given, I can calculate the difference between their volume changes $\Delta V$. However, this question did not provide the initial volume of mercury and glass.
The best I can do for this question, is to express the final answer in some unknown variable $x$