A calculator manufacturer offers two different models for students. The company has sold scientific calculators so far and continues to sell per month. It has also sold graphical models and continues to sell of this model each month. When will the sales of scientific calculators equal the sales of graphical calculators?

Let time (months) Write one expression for the number of scientific calculators sold and another expression for the number of graphical calculators sold after months.

Set your expressions equal to each other and solve for .