Rectangle dimension change

Scale both dimensions of the rectangle in the ratio 9:4. The original dimensions are 0.8 dm and 16 cm. What are the dimensions of the rectangle after the change?

Final Answer:

a =  3.5556 cm
b =  7.1111 cm

Step-by-step explanation:

$$\begin{gathered} x=0.8\text{dm}\to \text{cm}=0.8\cdot 10\text{cm}=8\text{cm} \\ y=16\text{cm} \\ k=4/9=\frac{4}{9}\doteq 0.4444 \\ a=k\cdot x=0.4444\cdot 8=\frac{32}{9}\text{cm}=3.5556\text{cm} \end{gathered}$$

$b=k\cdot y=0.4444\cdot 16=\frac{64}{9}\text{cm}=7.1111\text{cm}$

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