UNIT V MAT 1304
UnitV MAT 1304
Aninformal probability is critical since it helps in summarizing astate of knowledge. In informal probability, how much knowledge isavailable concerning a given item does not matter. It is feasible fora personal to make an informal probability within a short period,based on the level of confidence present, or one can spend a lot oftime searching for details concerning an item that he/she wants tomake an informal probability about (Tijms,2012). It is valid to assign a probability to something that one doesnot have numbers for, or for something that is underspecified.Therefore, providing an informal probability does not mean that anyrelated mathematical calculation has been carried out.
Anexample of an informal probability entails a situation where one istold to guess the probability of a red car passing in a certain roadthat he is not conversant with. In such a situation, one does nothave knowledge concerning the new road that is, one does not knowwhether there are any cars that pass on the new road. Besides, onedoes not know the number of cars that pass through the road. In thiscase, one may just give a probability based on a guess or a clue thatmay come in his mind. For example, without the need of estimating,one may say that the probability of a red car passing through theroad is “no car will pass on the road”. This is an informalprobability because it is given out of guess work. The person mayhave an assumption that because it is a new road, there will be nored car that will pass through the road. In short, this informalprobability has been used in expressing or summarizing a guess oravailable knowledge that a person has concerning a red car and thenew road.
Incase the probability of a red car passing through the new road was tobe done formally, calculations would be necessary (Lial et al, 2012).Besides, not only calculations would be necessary, but also availableknowledge concerning the new road and the cars that pass through theroad. When calculating the probability of a red car passing throughthe new road formally, it will be critical to know the total numberof cars that pass through the road. For example, knowledge about thenew road may be provided such that one is told that there are 1,000cars that pass through the road on a daily basis. Provided with thisclue, the probability of a red car passing through the new road wouldbe one dividing by the total number of cars that are estimated topass through the car therefore, the probability of a red car passingthrough the new road would be 1/1000. Depending with the availableknowledge that is provided, it is possible to calculate the differentprobabilities. It is critical noting that for a formal probability,numbers are involved and calculation is necessary nevertheless, somecalculations are simple, which do not require a lot of calculations.In case, the total number of red cars that pass through the new roadis known and the total number of cars that pass through the road isalso known, it is also possible to have a formal probability of a redcar passing. For example, consider a situation where 10 red cars passthrough the new road and the total number of cars that pass is 100then the probability of a red car passing is 10/100 = 1/10.
Lial,M. L., Greenwell, R. N., & Ritchey, N. P. (2012). Finitemathematics (10th ed.).Boston, MA: Pearson Education.
Tijms,H. C. (2012). Understandingprobability.New York: Cambridge University Press.