If x laborers can build a wall in t hours, then in terms of t how long

Question

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

BrentGMATPrepNow · Answer

Given : x laborers can build ONE wall in t hours
This means x laborers can build  EIGHT  walls in  8 t hours 
So,  3 x laborers can build EIGHT walls in 8 t / 3  hours

Answer:  C

Cheers,
Brent

HKD1710 · Answer

Solution with RT = W formula approach.

Given time =  t  and work  = 1  (wall)

xR * t   = 1

hence  R  =  \frac{1}{xt}

now the number of labors are 3x and work is 8 and time taken T is asked.

RT = W

3xR * T = 8

3x  *  \frac{1}{xt}   * T = 8

\frac{3T}{t}  = 8

T =   \frac{8t}{3}

Answer should be.   C

mohshu · Answer

x labourers can built 8 wallin in 8t hours,,,

3 times labouresr can build in 8t/3 hours

ans 8t/3

gracie · Answer

rate of 1 worker=1/xt
rate of 3x workers=3x/xt=3/t
8/(3/t)=8t/3=time for 3x workers to build 8 walls
C

JeffTargetTestPrep · Answer

We are given that x laborers can build a wall in t hours. Thus, the rate of the x laborers is 1/t and the rate for 3 times the number of laborers is 3/t. We need to determine how long it will take 3 times the number of laborers to build 8 walls. Thus:

time = work/rate

time = 8/(3/t) = 8t/3

Answer: C

fskilnik · Answer

?\,\, = \,\,f\left( t ight)\,\,\,\,\,\,\,\,\left

\begin{array}{*{20}{c}}
 {x\,\,{	ext{people}}} \ 
 {3x\,\,{	ext{people}}} 
\end{array}\,\,\,\,\,\,\begin{array}{*{20}{c}}
 {t\,\,{	ext{h}}} \ 
 {?\,\,{	ext{h}}} 
\end{array}\,\,\,\,\,\,\,\begin{array}{*{20}{c}}
 {1\,\,{	ext{job}}} \ 
 {8\,{	ext{job}}} 
\end{array}

\begin{array}{*{20}{c}}
 {} \ 
 {\left( { \cdot \,3} ight)} \ 
 {} 
\end{array}\,\,\,\,\begin{array}{*{20}{c}}
 {x\,\,{	ext{people}}} \ 
 {3x\,\,{	ext{people}}} \ 
 {3x\,\,{	ext{people}}} 
\end{array}\,\,\,\,\,\,\,\begin{array}{*{20}{c}}
 {t\,\,{	ext{h}}} \ 
 {t\,\,{	ext{h}}} \ 
 {?\,\,{	ext{h}}} 
\end{array}\,\,\,\,\,\,\,\begin{array}{*{20}{c}}
 {1\,\,{	ext{job}}} \ 
 {3\,\,{	ext{jobs}}} \ 
 {8\,\,{	ext{jobs}}} 
\end{array}

\left( {3x\,\,{	ext{people}}} ight)\,\,\,\,\,\, \downarrow \begin{array}{*{20}{c}}
 {t\,\,{	ext{h}}} \ 
 {?\,\,{	ext{h}}} 
\end{array}\,\,\,\,\,\, \downarrow \begin{array}{*{20}{c}}
 {3\,\,{	ext{jobs}}} \ 
 {8\,\,{	ext{jobs}}} 
\end{array}

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

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

Archit3110 · Answer

rate per worker ; 1/t and for 3 times worker 3/t
so for 8 walls time will be w= r*t 
t= 8t/3
IMO C

Kinshook · Answer

X laborers take t hours to build a wall
3x laborers will take t/3 hours to build a wall 
3x laborers will ale 8t/3 hours to build 8 walls

IMO C

Posted from my mobile device

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If x laborers can build a wall in t hours, then in terms of t how long

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If x laborers can build a wall in t hours, then in terms of t how long

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