houstonherdfan wrote:EVERYONE READ THE FOLLOWING. ALL OF IT NOT JUST PART OF IT
ALL OF YOU HAVE NOT GOTTEN THE POINT I WAS TRING TO MAKE. THAT IS:
When you teach the youth of our country to take the easy way out what do you get?
A bunch of adults that aren't worth a crap because they want everything easy. Work ethic goes to crap, parents don't raise their children, and just a general complete break down of basic respect for others.
Wait a minute we are already there. If I was single and had no family I would get the he--ll out of here before it gets any worse.
NOTE: BEFORE ANYONE THINKS THAT I AM SAYING THAT PI BEING ROUNDED IS RESPONSIBLE FOR THE STATE OF OUR CULTURE I AM NOT. IT IS JUST ONE EXAMPLE OF HOW SCREWED UP OUR CULTURE IS.
you should lead by example then. you should have used "are not" here instead of the contraction aren't...why use the shortcut, the easy way out?
NOTE: yes i'm being extremely petty here (and using contarctions myself ) but i dont see using 3 for Pi as any different than using "it's" instead if "it is"
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I'm a little confused as to why using 3 is considered a shortcut and 3.14 isn't. As with all irrational numbers, any rounding is technically a shortcut. The number 3.14 is just a more accurate value than 3, just as 3.1416 is more accurate than 3.14. Why one is considered acceptable and another is considered a sign that our schools are falling apart is beyond me.
Interestingly enough, given the way the problem is presented, using 3 for pi could actually be considered acceptable from a scientific or engineering point of view. The other inputs are all presented with one significant digit, so using ore than one for pi is unnecessary precision. The answer should be rounded and contain no decimals to match the precision level of the inputs.
3x2x1 = 6 3.14x2x1 = 6.28 which rounds to 6
If the calculation were (pi)x2.00x1.00, then pi would have to be taken to 3.14 or beyond.
Of course, this touches on some advanced mathematics, scientific, and engineering concepts and is a little much for a seventh grader, but it makes the point that using two decimal places is not universally right while the use of none is universally wrong.
At work (I'm an engineer), I use 3 for pi all the time when I am making estimates without a calculator. I'll multiply by three and then increase the result a little to account for the rounding. It is fast and accurate enough for the task. If I am doing an official calculation report, then I use however many decimal places are necessary to ensure that my pi estimate is not limiting the accuracy of my results. This means I almost always have to go way beyond two decimal places, so 3.14 would be just as wrong as 3.
As long as the student understands that pi is not exactly three and that it is in fact an irrational number somewhere between 3.1 and 3.2, I don't see a problem. If using 3 for pi in a problem allows the student more time to learn other topics (and the student understands that it is an estimate), then I can see the benefit.
There are plenty of other reasons/signs that our schools are screwed up, which is why my wife and I will be homeschooling our children. But, IMO, this isn't one of them.
As an interesting aside, one of the complaints I hear over and over again from experienced engineers concerning new engineers is that they use too many decimal places. The increasing use of computers and calculators has caused many young engineers to overlook the importance of significant digits. Excess precision is wasteful and it annoys the heck out of old engineers.
I'd like to see these kids round pi in their college courses. "But that's the way I was taught" isn't going to cut it. Fact is, if you're going to teach something, teach it correctly. It's like using modern English when teaching Shakespear. It's like teaching "lol" is an acceptable substitute for actually writing out laugh out loud.
In good news for schools today, my daughter was around average level reading when she started 1st grade this year, so her school put her in a program called Title 1, that helps accelerate reading and math skills. She didn't need the math, but imagine a school spending extra time and money on a child who's average to help her be better than average. She's an awesome reader now, with the work we have done with her and Title 1's help. I'm really interested to see where her reading level is at when they take their exams at the end of the year.
In bad news for schools, did anyone see the report about a month ago from Atlanta where school were using private grant money to PAY students to show up for tutoring? $8 an hour! Are you kidding me??? They didn't have to improve their grades or anything, just show up and pretend to work. What kind of message does that send all the kids who works hard to get better grades??
Munboy wrote:I'd like to see these kids round pi in their college courses. "But that's the way I was taught" isn't going to cut it. Fact is, if you're going to teach something, teach it correctly. It's like using modern English when teaching Shakespear. It's like teaching "lol" is an acceptable substitute for actually writing out laugh out loud.
Unless of course the college class allows the student to use 3 as pi. They aren't teaching kids that pi == 3. They are using it as an estimate, the same way we used 3.14 as an estimate. It's like focusing on teaching kids how to type 45 wpm instead of having great penmanship. It's like teaching kids how to use a search engine instead of the Dewy Decimal card catalog.
I was watching the Jimmy Kimmel show on Saturday and they had a sketch were Jimmy dressed up as George Washington and asked the students what the third president is known for.....one students answer was simply hilarious...it was...
I was talking to a middle school teacher today (she has been teaching now for 20 years) and she was venting about the TAKS test. She said that in her school (and most Texas schools she knows of) English isn't even taught for two entire years in college. She gets fifth graders that haven't learned sentence structure or even had to write out an entire sentence and get graded on it since they started school at all.
So apart from the original complaint (which I think is stupid they would do this as well) there are HUGE problems with the teaching in schools right now. As Madison said about them teaching too much information, she said that she is having to teach from 2nd grade English through 5th grade English all before March when they take the TAKS test.
houstonherdfan wrote:EVERYONE READ THE FOLLOWING. ALL OF IT NOT JUST PART OF IT
ALL OF YOU HAVE NOT GOTTEN THE POINT I WAS TRING TO MAKE. THAT IS:
When you teach the youth of our country to take the easy way out what do you get?
A bunch of adults that aren't worth a crap because they want everything easy. Work ethic goes to crap, parents don't raise their children, and just a general complete break down of basic respect for others.
Wait a minute we are already there. If I was single and had no family I would get the he--ll out of here before it gets any worse.
NOTE: BEFORE ANYONE THINKS THAT I AM SAYING THAT PI BEING ROUNDED IS RESPONSIBLE FOR THE STATE OF OUR CULTURE I AM NOT. IT IS JUST ONE EXAMPLE OF HOW SCREWED UP OUR CULTURE IS.
you should lead by example then. you should have used "are not" here instead of the contraction aren't...why use the shortcut, the easy way out?
NOTE: yes i'm being extremely petty here (and using contarctions myself ) but i dont see using 3 for Pi as any different than using "it's" instead if "it is"
Well, I could find you maybe 1000+ English textbooks that teach the use of contractions. If you can find me 1 Mathmatics textbook that teaches that it is OK to round pi and other constants, I'll apologize for my ranting on this subject.
You could think of government workers like teenagers. You pay them an allowance, but do you get any work out them? They eat the food, put their feet on the furniture and complain loudly whenever they are unhappy.
pvt1863 wrote:I'm a little confused as to why using 3 is considered a shortcut and 3.14 isn't. As with all irrational numbers, any rounding is technically a shortcut. The number 3.14 is just a more accurate value than 3, just as 3.1416 is more accurate than 3.14. Why one is considered acceptable and another is considered a sign that our schools are falling apart is beyond me.
Interestingly enough, given the way the problem is presented, using 3 for pi could actually be considered acceptable from a scientific or engineering point of view. The other inputs are all presented with one significant digit, so using ore than one for pi is unnecessary precision. The answer should be rounded and contain no decimals to match the precision level of the inputs.
3x2x1 = 6 3.14x2x1 = 6.28 which rounds to 6
If the calculation were (pi)x2.00x1.00, then pi would have to be taken to 3.14 or beyond.
Of course, this touches on some advanced mathematics, scientific, and engineering concepts and is a little much for a seventh grader, but it makes the point that using two decimal places is not universally right while the use of none is universally wrong.
At work (I'm an engineer), I use 3 for pi all the time when I am making estimates without a calculator. I'll multiply by three and then increase the result a little to account for the rounding. It is fast and accurate enough for the task. If I am doing an official calculation report, then I use however many decimal places are necessary to ensure that my pi estimate is not limiting the accuracy of my results. This means I almost always have to go way beyond two decimal places, so 3.14 would be just as wrong as 3.
As long as the student understands that pi is not exactly three and that it is in fact an irrational number somewhere between 3.1 and 3.2, I don't see a problem. If using 3 for pi in a problem allows the student more time to learn other topics (and the student understands that it is an estimate), then I can see the benefit.
There are plenty of other reasons/signs that our schools are screwed up, which is why my wife and I will be homeschooling our children. But, IMO, this isn't one of them.
As an interesting aside, one of the complaints I hear over and over again from experienced engineers concerning new engineers is that they use too many decimal places. The increasing use of computers and calculators has caused many young engineers to overlook the importance of significant digits. Excess precision is wasteful and it annoys the heck out of old engineers.
Of all the responses this is the first one that had any thought and mathmatical basis too it. Your point of significant digits is correct in the way I wrote it. Thinking back I am not sure how it was actual stated on my son's paper. I will bring it up as a question when I meet with the Principal and the head of the math dept at my son's school tomorrow. However, if significant digits was the reason for rounding pi to 3 why didn't the teacher just say so at some point during our conversation. We discussed enough about the subject of math that she should have been aware that I would have understood should she have chosen to discuss it.
I do have one question, significant digits aside. Is not the standard number of digits taught in the basic textbooks 3.14?
You could think of government workers like teenagers. You pay them an allowance, but do you get any work out them? They eat the food, put their feet on the furniture and complain loudly whenever they are unhappy.