Question

When the mortgage is completely paid off for Mark and Lynne’s house, it will be 6 times as old as it is now. If they have 25 years left on the mortgage, how old is the house right now?

Answer 1

Let us take the age of the house currently as x.

The second statement says that the house will be 6 times as old as it is now after payment is completed.

If the mortgage will be completed in 25 years, we can write that mathematically as

$6x=x+25$

Therefore, the age of the house, x, can be calculated as

$\begin{gathered} 6x-x=25 \\ 5x=25 \\ x=\frac{25}{5} \\ x=5 \end{gathered}$

Hence, the house is 5 years old now.