Decorative 11881

Mrs. Koláčkova wants to decorate the walls of her room with a strip of wallpaper 5 cm wide. How many meters of this decorative strip will he have to buy if the shorter side of the room measures 3 m and the longer side measures twice as much?

Correct answer:

x =  18 m

Step-by-step explanation:

$$\begin{gathered} a=3\text{m} \\ b=2\cdot a=2\cdot 3=6\text{m} \\ x=2\cdot (a+b)=2\cdot (3+6)=18\text{m} \end{gathered}$$

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