If x men working x hrs/day can do x units of work in x days, then y men working y hrs/day would be able to complete how many units of works in y days:
x^2/y^3
x^3/y^2
y^2/x^3
x^2/y^3
y^3/x^2
x/y^3
x^2/y^3
x^3/y^2
y^2/x^3
x^2/y^3
y^3/x^2
x/y^3
















