estimate

eddy2017 said:
I know the minimum and maximum speed from Swanson to Dennison, which is
40 mph * 3 h= 120 miles
60 mph* 3h= 180miles

but the total minimum or max speed don't know.
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Re-read your problem again. It says:

"...lee then drove from Dennison to Westport in 1 hour without stopping. His speed on this part of the trip varied from 20mph to 40 mph. "

Your main problem is that you do not read "critically" and thus your answers become incoherent. You even wrote these out in your "given"s - probably "copy and paste" without paying attention.

So:

what is the maximum distance from Dennison to Westport?​
​
what is the maximum distance from Dennison to Westport?​
 
Subhotosh Khan said:
Re-read your problem again. It says:

"...lee then drove from Dennison to Westport in 1 hour without stopping. His speed on this part of the trip varied from 20mph to 40 mph. "

Your main problem is that you do not read "critically" and thus your answers become incoherent. You even wrote these out in your "given"s - probably "copy and paste" without paying attention.

So:

what is the maximum distance from Dennison to Westport?​
​
what is the maximum distance from Dennison to Westport?​
Click to expand...
maximum distance 40 miles.
Sorry I was having supper.
 
The same thing happened again, same as last night. We agreed on a result through a reasoning and then everything goes south.
 
I will go to bed now. Will re -read everything again in the morning. Thanks for your help. I really appreciate it!.
 
eddy2017 said:
The same thing happened again, same as last night. We agreed on a result through a reasoning and then everything goes south.
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I apologize. Prof Khan asked for two speeds. I just never assumed it was for the same speeds. Again, I am sorry for my last post.
 
Jomo said:
I apologize. Prof Khan asked for two speeds. I just never assumed it was for the same speeds. Again, I am sorry for my last post.
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You don't need to apologize Mr Jomo. Not at all, not one bit!!. I will re-read everything again tomorrow morning. It is too late now. Thank you so much for your hints and help. To all of you.
 
eddy2017 said:
You don't need to apologize Mr Jomo. Not at all, not one bit!!. I will re-read everything again tomorrow morning. It is too late now. Thank you so much for your hints and help. To all of you.
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I told you that you did something wrong and you did not. I feel that deserves an apology. Good night.
 
eddy2017 said:
Just pure logic. Driving at 40 mph * 3h = 120 miles cos the hrs cancel out
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Here's what you tried first:
"A reasonable guess would be 2,400 miles. Multiplying 40 * 60 to find that estimate"
I don't see any logic there. Let me know whether you want to go over this problem in a more systematic manner. Or you can pick a new problem.
 
I
lev888 said:
Here's what you tried first:
"A reasonable guess would be 2,400 miles. Multiplying 40 * 60 to find that estimate"
I don't see any logic there. Let me know whether you want to go over this problem in a more systematic manner. Or you can pick a new problem.
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I want to finish it, please. Let me re-read everything and put it together on a piece of paper and I will get back to you. Thanks Mr Lev for staying with it till the end.
 
Eddy

I have written twice now on how to solve word problems, which are the key to using math for any practical purpose. And the first step is to THINK. (In fact, learning to think systematically in lev’s words may be the most important thing taught in math class for 90% of students.) We do this before we even try to use any mathematical tools such as arithmetic, algebra, calculus, etc. Until we have thought, we do not even know whether any mathematical tools are necessary, and we certainly do not not know which mathematical tools might be useful. You do not grab a hammer if your mother asks for help fixing supper.

So how do we think systematically? We read the problem carefully, more than once if necessary, to be sure we fully understand it. We ask ourselves what extra-mathematical ideas (outside mathematics proper) seem to be involved. Here it is the meaning of the phrase “reasonable estimate.” If I asked you to tell me what a “reasonable estimate” is, what would you say? You certainly cannot find something if you do not know what it is.

Please tell me in your own words what you think a reasonable estimate is.
 
A reasonable estimate (of something) when given in a problem does not exceed the original numbers in a problem. It has to be within the confines of the amounts given. That I found online while searching if there was a formula when we needed to find distance with non-uniform speeds, speeds that are not constant. I could not find anything about that though.
 
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Jomo said:
You asked me to make an estimate of the speed. I did. 50 miles. Oh, wrote 150. Sorry. it's 50 miles
average speed 50 miles * 3 h =150 miles
From Dennison to Weston the average is 30 * 1h=30

Everything you wrote above is wrong.

Average speed 50miles*3hrs = 150 miles: First average speed is a speed and a speed is distance/time as in miles/hour NOT miles*hrs as you wrote. 50 miles *3 hrs does NOT equal 150 miles. 50 miles * 3 hrs = 150 miles* hrs (whatever that means)

From Dennison to Weston the average is 30 * 1h=30: No, 30*1hr does NOT equal 30. 30 *1 = 30! For the record, 30* 1hr = 30 hrs.
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Lee drove from Swanson to Dennison in 3 hours without stopping. His driving speed varied from 40 miles per hour to 60 mph. lee then drove from Dennison to Westport in 1 hour without stopping. His speed on this part of the trip varied from 20mph to 40 mph.


at this post I wrote that an average speed from Swanson and Dennison could be 50 miles.
that 50 mph * 3hrs= 150 miles ( estimated distance covered between Swanson to Dennison in 3 hours)
then, i concluded that from Dennison to Weston an estimated speed was 30 mph.
and that 30pmh * 1hr drive =30 miles.
then, adding up both amounts 150 miles+30 miles=180 ( reasonable estimate of the total of miles covered) .
I think you said this reasoning was good, after correcting the units, or not?. Is it good or not?.
 
eddy2017 said:
Lee drove from Swanson to Dennison in 3 hours without stopping. His driving speed varied from 40 miles per hour to 60 mph. lee then drove from Dennison to Westport in 1 hour without stopping. His speed on this part of the trip varied from 20mph to 40 mph.


at this post I wrote that an average speed from Swanson and Dennison could be 50 miles.
that 50 mph * 3hrs= 150 miles ( estimated distance covered between Swanson to Dennison in 3 hours)
then, i concluded that from Dennison to Weston an estimated speed was 30 mph.
and that 30pmh * 1hr drive =30 miles.
then, adding up both amounts 150 miles+30 miles=180 ( reasonable estimate of the total of miles covered) .
I think you said this reasoning was good, after correcting the units, or not?. Is it good or not?.
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It looks good. I just have one question. You say reasonable estimate of the total of miles covered. Why do you think it is reasonable? That is exactly what did you do or think to make this conclusion? Please be precise.
 
Jomo said:
It looks good. I just have one question. You say reasonable estimate of the total of miles covered. Why do you think it is reasonable? That is exactly what did you do or think to make this conclusion? Please be precise.
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Jomo said:
It looks good. I just have one question. You say reasonable estimate of the total of miles covered. Why do you think it is reasonable? That is exactly what did you do or think to make this conclusion? Please be precise.
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I used the mean.
adding up both amounts and divinding it by 2 ( 2 being the total number of points in the data set, in this case both speeds in mph.
40 + 60 =100/2 =50
20 + 40 =60/2 =30
that is how I found it.
 
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