Final answer:
The dealer's markup amount is $26,100 and the original cost of the RV is $31,900.
Step-by-step explanation:
To determine the dealer's markup, we need to find 45% of the selling price of the RV. We can set up the following equation:
Markup amount = Selling price × Markup percentage
Let's plug in the given values: $58,000 × 45% = $26,100
The dealer's original cost can be found by subtracting the markup amount from the selling price:
Original cost = Selling price - Markup amount
Let's calculate it: $58,000 - $26,100 = $31,900