Last year's salary was $46,500.
Work Step by Step
First, we need to define our unknown. What we want to find out is last year's salary, which we shall designate as $x$: This will be our unknown. We will need to add the amount of the salary increase to last year's salary to get this year's salary of $50,220$ dollars. Because the amount of the salary increase is $8$%, the amount of the increase can be given by the expression (8%)$(x)$. We cannot work directly with percentages, so we change the percent into a decimal. We do this by dividing the percentage by $100$ to get rid of the percentage sign. The percentage becomes $0.08$. We can now set up the following equation to find last year's salary: $$x + 0.08x = 50,220$$ We combine like terms: $$1.08x = 50,220$$ To solve for $x$, we divide both sides of the equation by $1.08$: $$x = 46,500$$ Last year's salary was $46,500.