Final answer:
The markup from cost to sale is $348.57.
Step-by-step explanation:
To find the markup from cost to sale, we need to calculate the original selling price before the 30% markdown. Let's assume the cost price is 'C', and the original selling price is 'S'.
The selling price after the 30% markdown is 440, which is 70% of the original price:
S - 30% of S = 440
Solving this equation, we find that the original selling price is 628.57 (approximately).
Therefore, the markup from cost to sale is S - C = 628.57 - 280 = $348.57.