Cups of paint

I have a board that is 2 meters wide and 3 meters tall. Suppose one cup of paint cover 1,000 square centimeters. How many cups of paint do I need?

Correct answer:

x =  60

Step-by-step explanation:

$$\begin{gathered} a=2\text{m}\to \text{cm}=2\cdot 100\text{cm}=200\text{cm} \\ b=3\text{m}\to \text{cm}=3\cdot 100\text{cm}=300\text{cm} \\ S=a\cdot b=200\cdot 300=60000{\text{cm}}^2 \\ {S}_1=1000{\text{cm}}^2 \\ x=S/S_1=60000/1000=60 \end{gathered}$$

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