36 persons can repair a road in 12 days, working 5 hours a day. In how many days will 30 persons, working 6 hours a day, complete the work?  Choose the correct choice from the following choices
A) 12  B) 16  C) 13  D) 18  E) 19
Let the required number of days be x.   Less persons, More days (Indirect Proportion)   More working hours per day, Less days (Indirect Proportion)   Persons 30 : 36 :: 12 : x   Working hours/day 6 : 5   30 x 6 x x = 36 x 5 x 12   x = (36 x 5 x 12)/(30 x 6)   x = 12   12NSWER 12
<result>A</result>
36 persons can repair a road in 12 days, working 5 hours a day. In how many days will 30 persons, working 6 hours a day, complete the work?