From: Xun Chen
To: Teacher2Teacher Public Discussion
Subject: More on Front End Estimation
Thank you for your feedback, but you didn't get to the point. To show an extreme case, considering $182,804,050.32 + $1, if we use the method I shown in my first question, we will come up with a range of $100,000,001 as the lower end, and $200000002 as the higher end. Yes, the real number is indeed inside the ranges derived from various approaches, but which what gives a more suitable picture of it? My believe is if we use front-end estimation and expect it to be useful, we should make sure the numbers are in the same order. A good example will be like: $290.94 + $146.53+ $313.83 If they are not in the same order, I suggest either zero be added to the left side of the number, so that they appear in the same order, Question 13) $290.94 + $104.53 + $3.83 will become $290.94 + $104.53 + $003.83 Thus, when we apply the current method, we will get 200+100+0 for the lower end and 300+200+100 for the higher end for the range. Or, more than one digit be used in this method, in our case, using two digits will be very reasonable. Question 13) $290.94 + $140.53 + $3.83 will have 290+140+0 for the lower end and 300+150+10 for the higher end for the range.
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