Nina used

Nina used 2 liters of paint to paint a wall. The wall was a rectangle 2 meters high and 4 meters wide. How many liters of paint would she need to paint a rectangular wall which is 2.5 meters high and 8 meters wide?

Final Answer:

V₂ =  5 l

Step-by-step explanation:

$$\begin{gathered} V_1=2\text{l} \\ a=2\text{m} \\ b=4\text{m} \\ c=2.5\text{m} \\ d=8\text{m} \\ {S}_1=a\cdot b=2\cdot 4=8{\text{m}}^2 \\ {S}_2=c\cdot d=2.5\cdot 8=20{\text{m}}^2 \\ {V}_2=V_1\cdot \frac{S_2}{S_1}=2\cdot \frac{20}{8}=\frac{2\cdot 20}{8}=\frac{40}{8}=5\text{l} \end{gathered}$$

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