10 men working 6 hrs per day manufacture 200 shoes in 18 days. How many hours a day must 15 men work to manufacture the same 200 shoes in 12 days?	Choose one.
A) 6 B) 10 C) 12 D) 15 E) 18
Let the required number of hours be x.   More men, less hours per day (Indirect proportion)   Less days, more working hours per day (Indirect proportion)   men 15 : 10   } : : 6 : x   days 12 : 18   .'. 15*12*x = 10*18*6   = x = 10*18*6/(15*12)   = x = 6 6NSWER : 6
<result>A</result>
10 men working 6 hrs per day manufacture 200 shoes in 18 days. How many hours a day must 15 men work to manufacture the same 200 shoes in 12 days?