The width of the rectangle a b c d below is equal to one third of its length, and its perimeter equals 64 cm. What is the area of the shaded parts in square centimeters?

The image is not the exact one, I mean the measurements are not correctly marked but the shading is right. I want to find the area of the blue regions

• $12$ is not one third of $18$ – Henry Jul 31 '16 at 9:45
• What is known about the white triangle? It's base appears smaller than the length of the rectangle. Is the apex a right angle? – Jens Jul 31 '16 at 10:38
• How is the top vertix of the triangle placed? without that information one cannot answer – VictorZurkowski Jul 31 '16 at 10:43
• Sorry I couldn't find the correct diagram! I got it though! Thanks :) – Hana Jul 31 '16 at 13:36

Then the perimeter of the rectangle would be $8s$ and if this were $64\,cm$ then $s=8\,cm$ and $3s=24\,cm$ making the area of the rectangle $192\,cm^2$ and the blue area half that namely $96\,cm^2$