### Home > INT1 > Chapter 5 > Lesson 5.2.3 > Problem5-82

5-82.

A calculator manufacturer offers two different models for students. The company has sold $10\text{,}000$ scientific calculators so far and continues to sell $1500$ per month. It has also sold $18\text{,}000$ graphing calculators and continues to sell $1300$ of this model each month.

1. If at some month, m, the number of scientific calculators sold is equal to the number of graphical calculators sold, then write an equation that represents this situation.

Write an expression representing the number of scientific calculators in terms of the number of months ($m$).

Total number of scientific calculators sold so far: $10000 + 1500m$

Now, write an expression for the graphing calculators.

2. When will the number of scientific calculators sold equal the number of graphical calculators sold? That is, solve your equation from part (b) for $m$.

$m = 40$, meaning that in the $40th$ month, they will have sold the same number of scientific calculators and graphing calculators.