Question

If 7 gallons of paint are needed to paint 4 rooms. How many gallons of paint will they need to paint 11? set up the proportion then solve it.

Answer 1

Given the information, we have a direct proportionality. Then, the proportions would be:

$\frac{7}{x}=\frac{4}{11}$

solving for x we get the following:

$\begin{gathered} \frac{7}{x}=\frac{4}{11} \\ \Rightarrow7=\frac{4}{11}\cdot x \\ \Rightarrow\frac{7}{\frac{4}{11}}=x \\ \Rightarrow x=\frac{11\cdot7}{4}=\frac{77}{4}=19\frac{1}{4} \\ x=19\frac{1}{4} \end{gathered}$

therefore, to paint 11 rooms, we will need 19 1/4 gallons of paint