A spreadsheet term.
Goal seek allows you to set a 'goal' in one cell and tell the spreadsheet to reach it by altering the value in another cell.
The Goal seek function will 'tweak' the other cell and examine the effect on the goal cell's value. If it is now closer to the goal, then a little bit more is added and so on, until the goal is reached.
Goal seek is very handy for finding the best solution when there are many things you can tweak to get there.
Challenge see if you can find out one extra fact on this topic that we haven't already told you
Click on this link: Goal Seek