I was looking for a general way of formulating solutions for work and time problems.
30 soldiers can dig 10 trenches of size 8*3*3 ft in half a day working 8 hours per day. How many hours will 20 soldiers take to dig 18 trenches of size 6*2*2 ft working 10 hours per day?
Now i know that Work = Efficiency * Time, but i get confused sometimes in selecting which factor in the given problem will contribute directly to the work i.e. increase it and which factors will result in the work being done faster.
I've seen the method in which one uses a table to write all the parameters given in the problem e.g. making columns titled work, number of soldiers, volume of trench, number of days required, number of hours per day, efficiency, wages etc and uses the direct and inverse proportionality to write the equation for solving a given unknown. However i face the same problem i.e. finding out which factors are directly related and which are in an inverse relation.
Is there a simple way of solving these general problems?