Answer vs Problem

In school, we are trained to find an exact answer, and we always can as long as we do it the right way... In the real working and social world, sometimes, the same answer can't be used for the same problem.... Sometimes, there are few answers for a problem, whereas sometimes, there is no answer at all...WHY?

In school, problems are made based on answer... So, there will always be only one answer for each problem... Also, sufficient and ideal initial & boundary conditions are always provided... Jumping out from school, problem is always there for us to solve, therefore different person, different approach may get different answer in the end... Moreoever, we must always pay our effort to find out the initial conditions... And most of the tme, we suffer when finding this, and sometimes, the conditions found are not reasonable at all... OUCH!