x men working x hours per day can do x units of a work in xx days. How much work can be completed by y men working y hours per day in y days?  Pick one:
A) x2/y2 units	B) y3/x2 units	C) x3/y2 units	D) y2/x2 units	E) None
Explanation:   Let amount of work completed by y men working y hours per in y days = w units   More men, more work(direct proportion)   More hours, more work(direct proportion)   More days, more work(direct proportion)   Hence we can write as   (men)x:y   (hours)x:y   (days)x:y }::x:w   ⇒x^3w=y^3x   ⇒w=y^3x/x^3   =y^3/x^2   Answer: Option y3/x2 units
<result>B</result>
x men working x hours per day can do x units of a work in xx days. How much work can be completed by y men working y hours per day in y days?