Answer
$5.9\%$.
Work Step by Step
The given values are
Sell price $m=\$20,400$.
Offer price $s=\$19,200$.
Reduction in the price
$=m-s$
$=\$20,400-\$19,200$
$=\$1,200$.
Percent reduction
$=\frac{1,200}{20,400}\times 100$
Simplify.
$=5.88235294118$
Rounded value.
$=5.9\%$.
