To answer this question, we can see that we have the volume of the rectangular fish tank. We also know that 1 milliliter is equal to 1 cubic centimeter. Then, we can proceed to find the length of the width of the rectangular fish tank as follows:
[tex]1ml=1\operatorname{cm}\Rightarrow904.5ml=904.5\operatorname{cm}^3[/tex]Then, we can say that:
[tex]904.5\operatorname{cm}^3=l\cdot h\cdot w\Rightarrow\begin{cases}l=15\operatorname{cm} \\ h=9\operatorname{cm} \\ w=\text{?}\end{cases}[/tex]Then, if we substitute each of the values into the equation, we have:
[tex]904.5\operatorname{cm}^3=15\operatorname{cm}\cdot9\operatorname{cm}\cdot w[/tex]If we divide both sides of the equation by 15cm*9cm, we solve the equation for the unknown, w, as follows:
[tex]\frac{904.5\operatorname{cm}^3}{15\operatorname{cm}\cdot9\operatorname{cm}}=\frac{15\operatorname{cm}\cdot9\operatorname{cm}}{15\operatorname{cm}\cdot9\operatorname{cm}}\cdot w[/tex][tex]\frac{904.5cm^2cm}{135\operatorname{cm}^2}=w\Rightarrow w=6.7\operatorname{cm}[/tex]Then, we have that the width of the fish tank is 6.7cm.
In summary, we have that the width of the fish tank is 6.7 cm (option B).
