T2T || FAQ || Ask T2T || Teachers' Lounge || Browse || Search || Thanks || About T2T
View entire discussion
[<< prev] [ next >>]
From: Doug To: Teacher2Teacher Public Discussion Date: 2005111905:25:01 Subject: Re: Re: Re: Give me a break! I do construction estimation for a living and this has nothing to do with it! Our estimation has to do with materials prices going up during the project. The real point is that parents can't help their children with this because we were never tought this method. Your solution leaves us to either 1)yell at our children for not knowing how to do it, 2) tell them to skip it, or 3)tell them to just guess. I'm not going to do any of those. The fact of the matter is, the teacher still wants their correct answer, and I went to many sites like this on the internet to learn how to help my son and found many variations to this method. Had he not forgotten his book in school, I would have helped him from the book. But not knowing what method his book uses I could'nt help. In the "real" world when I see a price for $6.29 another for $6.29 and a third for $3.55, what I do very quickly in my head is this, 6.29 and 6.29 is 13 and 3.55 makes it $16.55. I believe thats simple enough! the true answer? $16.13! If I want to know if I have enough money this covers me. and if I want to correct for tax I would simply make the 3.55 into 4.00. In my case 6% sales tax makes it $17.10 and my original figures only come in .10$ short, thats alot better than $15.00 which leaves me $2.10 short. Now back to construction estimates. If you built a house that costs $100,000, and I used your front end estimation you would have me in court or I would be bankrupt! There are alot more usful things that can be taught in schools than an admitidly flawed formula. do you know how many adults and teens can't read a tape measurer? How about spending the time on something useful like reviewing subject matter with students who fail tests since they obviously don't know it, instead of marking F and going on? when I was in grade school math teachers taught us to figure percentages in our heads, and that has been very useful in life. Teach them the correct way not the easy way.
Math Forum Home || The Math Library || Quick Reference || Math Forum Search