24 persons can manufacture 1000 soaps in 15 days, working 7 hours a day. In how many days will 18 persons, working 5 hours a day, manufacture the same 1000 soaps?  Choose the correct choice from the following answers.
A) 30	B) 28	C) 35	D) 14	E) 21
Explanation :   Solution: Let the required number of days be x.   Less persons, more days (Indirect proportion)   more working hrs per day, less days (indirect proportion)   persons 18 : 24   } : : 15 : x.   Working hrs per day, less days 5 : 7   .'. 18*5*x = 24*7*15 &lt;=&gt; x = 28.   Answer : 28
<result>B</result>
24 persons can manufacture 1000 soaps in 15 days, working 7 hours a day. In how many days will 18 persons, working 5 hours a day, manufacture the same 1000 soaps?