10 men, working 6 hours a day can complete a work in 18 days. How many hours a day must 15 men work to complete the work in 12 days ? Choose the correct choice from the following choices: A) 2hours a day B) 7hours a day C) 6hours a day D) 3hours a day E) 2hours a day
Explanation:   More Men, Less Hours {Indirect Proportion}   Less Days, More Hours {Indirect Proportion}   \inline {\color{Blue} \begin{bmatrix} Men &amp;15 &amp; 10\\ Days &amp;12 &amp; 18 \end{bmatrix}::6:x}   =&gt; x * 15 * 12 = 10 * 18 * 6   =&gt; x = (10 *18 *6)/(12*15)   =&gt;x = 6   Answer: 6hours a day
<result>C</result>
10 men, working 6 hours a day can complete a work in 18 days. How many hours a day must 15 men work to complete the work in 12 days ?