Answer :
Word Problem on Proportion.
[tex]\begin{gathered} C=15\text{ \% 0f D} \\ C\text{ = }\frac{15}{100}D \\ C=0.15D \end{gathered}[/tex]The correct answer is C = 0.15D
The constant of proportionality of the equation is 0.15
b. The constant of proportionality being 0.15 implies that 0.15 of Lee's total sales of electronics gives Lee's commission.
To find D when C = $450.
We simply substitute 450 for C in the above equation,
[tex]\begin{gathered} C=0.15D \\ 450=\text{ 0.15D} \\ \text{Divide both sides by 0.15, we get} \\ \frac{450}{0.15}=D \\ \\ D=\frac{450}{0.15}=\text{ \$3000} \end{gathered}[/tex]Lee needs to sell $3,000 worth of electronics to earn a commission of $450.
So, the correct answer is $450.