Answer:
$1214.19
Explanation:
Let c and p represent the cost of the sofa and the original selling price, respectively. The original markup was 0.69·p, so we have ...
c + 0.69p = p . . . . . based on selling price, the original markup was 69%
c = p(1 -0.69) = 0.31p . . . . subtract the markup
p = c/0.31 . . . . . . . . . . . . . divide by the coefficient of c
So, the original selling price was ...
520/0.31 ≈ 1677.42
The first markdown decreased the selling price to ...
1677.42 - 0.13·1677.42 = 0.87·1677.42 ≈ 1459.36
The markup increased the selling price to ...
1459.36 +0.30·1459.36 ≈ 1897.17
And the final markdown decreased the selling price to ...
1897.17 -0.36·1897.17 ≈ 1214.19
The final sale price was $1214.19.