Bunuel wrote:

If x laborers can build a wall in t hours, then in terms of t how long would it take 3 times the number of laborers to build eight walls?

A. t/24

B. 3t/8

C. 8t/3

D. 8t

E. 24t

\(?\,\, = \,\,f\left( t \right)\,\,\,\,\,\,\,\,\left[ {\text{h}} \right]\)

\(\begin{array}{*{20}{c}}

{x\,\,{\text{people}}} \\

{3x\,\,{\text{people}}}

\end{array}\,\,\,\,\,\,\begin{array}{*{20}{c}}

{t\,\,{\text{h}}} \\

{?\,\,{\text{h}}}

\end{array}\,\,\,\,\,\,\,\begin{array}{*{20}{c}}

{1\,\,{\text{job}}} \\

{8\,{\text{job}}}

\end{array}\)

\(\begin{array}{*{20}{c}}

{} \\

{\left( { \cdot \,3} \right)} \\

{}

\end{array}\,\,\,\,\begin{array}{*{20}{c}}

{x\,\,{\text{people}}} \\

{3x\,\,{\text{people}}} \\

{3x\,\,{\text{people}}}

\end{array}\,\,\,\,\,\,\,\begin{array}{*{20}{c}}

{t\,\,{\text{h}}} \\

{t\,\,{\text{h}}} \\

{?\,\,{\text{h}}}

\end{array}\,\,\,\,\,\,\,\begin{array}{*{20}{c}}

{1\,\,{\text{job}}} \\

{3\,\,{\text{jobs}}} \\

{8\,\,{\text{jobs}}}

\end{array}\)

\(\left( {3x\,\,{\text{people}}} \right)\,\,\,\,\,\, \downarrow \begin{array}{*{20}{c}}

{t\,\,{\text{h}}} \\

{?\,\,{\text{h}}}

\end{array}\,\,\,\,\,\, \downarrow \begin{array}{*{20}{c}}

{3\,\,{\text{jobs}}} \\

{8\,\,{\text{jobs}}}

\end{array}\)

\(\frac{?}{t} = \frac{8}{3}\,\,\,\,\, \Rightarrow \,\,\,\,\,? = \frac{{8t}}{3}\)

The above follows the notations and rationale taught in the GMATH method.

_________________

Fabio Skilnik :: GMATH method creator (Math for the GMAT)

Our high-level "quant" preparation starts here: https://gmath.net