Question 703136
<pre>

Here's another way to do it.

Use the worker-time-job formula, which is:

{{{(W[1]T[1])/J[1]}}}{{{""=""}}}{{{(W[2]T[2])/J[2]}}}

where

W<sub>1</sub> = the number of workers in the first situation.
T<sub>1</sub> = the number of time units (days in this case) in the first situation.
J<sub>1</sub> = the number of jobs in the first situation.

W<sub>2</sub> = the number of workers in the second situation.
T<sub>2</sub> = the number of time units (days in this case) in the second situation.
J<sub>2</sub> = the number of jobs in the second situation.

W<sub>1</sub> =  6             W<sub>2</sub> = 3     
T<sub>1</sub> =  6             T<sub>2</sub> = the unknown quantity 
J<sub>1</sub> =  6             J<sub>2</sub> = 2

{{{(W[1]T[1])/J[1]}}}{{{""=""}}}{{{(W[2]T[2])/J[2]}}}

{{{(6*6)/6}}}{{{""=""}}}{{{(3*T[2])/2}}}

{{{36/6}}}{{{""=""}}}{{{(3*T[2])/2}}}

{{{36/6}}} reduces to {{{6}}}

{{{6}}}{{{""=""}}}{{{(3*T[2])/2}}}

Multiply through by 2

{{{12}}}{{{""=""}}}{{{3*T[2]}}}

Divide both sides by 3

 4 = T<sub>2</sub> 

Answer: 4 hrs.

Edwin</pre>