You can use the Goal Seek add-on to calculate the required value of a cell to achieve a desired value in another cell. This is particularly useful when conducting break-even analysis or sensitivity calculations, like determining how changing one value affects other correlated values in your sheet.
Interesting to see Google extending the functionality of Google Sheets with this official add-on
Source: G Suite Updates Blog: Goal Seek add-on now available for Google Sheets
Member of Google Developers Experts Program for Google Workspace (Google Apps Script) and interested in supporting Google Workspace Devs.