Cuboid - edges

The sum of all edges cuboid is 31 meters. However, the width is twice shorter as the length, and the height is seven times longer than the width. Determine the dimensions of the cuboid.

Final Answer:

a =  3.1 m
b =  6.2 m
c =  21.7 m

Step-by-step explanation:

$$\begin{gathered} a+b+c=31 \\ a=b/2 \\ c=7a \\ b/2+b+7a=31 \\ \frac{b}{2}+b+7\cdot \frac{b}{2}=31 \\ b/2+b+7\cdot b/2=31 \\ 10b=62 \\ b=\frac{62}{10}=6.2 \\ b=\frac{31}{5}=6.2 \\ a=b/2=6.2/2=3.1\text{m} \end{gathered}$$

$c=7\cdot a=7\cdot 3.1=21.7\text{m}$

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