Both regular octagons are similar, so we can apply the concept of similar shape regarding the length of the side and the area.
If the scale factor of side is 'n' then the scale factor of the area is 'n²'
Octagon A's side length = 10.9
Octagon B's side length = 16.35
Scale factor of side length = 16.35 ÷ 10.9 = 1.5
Scale factor of area = 1.5² = 2.25
Area of octagon A = 392.4
Area of octagon B = 392.4 × 2.25 = 882.9 in²
Correct answer: B