Question

Mario has saved $200 towards the cost of buying a $1000 computer. In the weeks to come, he plans to save an additional $30 per week. Write an algebraic expression to represent the total amount he still needs to save after w weeks have passed.

Answer 1

The equation would be A = 30w + 200.

Since the base he already has is 200, then we know it needs to be the constant. The rate per week is always multiplied by the variable, which in this case is w.

Now to solve for what he is purchasing (a computer for $1000), we put the cost in for A.

1000 = 30w + 200

800 = 30w

26.67 = w

So if we are rounding up to whole number of weeks, the answer is 27