#### Answer

The dealer's cost of the refrigerator is $ \$ 467.2 $.

#### Work Step by Step

Let $ x $ represents the dealer's cost of the refrigerator.
$ 25 \% $ of the dealer's cost is $ = (0.25)x $.
The selling price of a refrigerator is $ \$ 584 $ per night.
In mathematical form.
$ x+0.25x=584 $
$ (1+0.25)x=584 $
$ 1.25x=584 $
$ x=\frac{584}{1.25} $
$ x=467.2 $.