Question

In the past you paid $800 per month to rent your apartment you now paid $900 per month what is the percent increase in your rent.

Answer 1

$\frac{Change}{Original} * 100\\\\\frac{100}{800}*100=\frac{100}{8}=\frac{25}{2}\\\\25/2=12.5$

The change was 12.5%.