Answer
There was a $23.21\%$ increase in floor space.
Work Step by Step
RECALL:
$\text{percent increase}=\dfrac{\text{increase in value}}{\text{original value}}$
The given problem has:
original value =$28,000$ square feet
increase in value = $6,500$ square feet
Solve for the percent increase using the formula above to obtain:
percent increase
$= \dfrac{6,500}{28,000}
\\=0.2321428571
\\=0.2321428571 \times 100\%
\\=23.21428571\%
\\\approx 23.21\%$
Thus, there was a $23.21\%$ increase in floor space.