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Russia has like 9 time zones...does this problem take that into account?
I guess you have to assume that the cities are directly north-south from each other and located in the same time zone in order to get a nice neat answer. And that's something that I want my future scientists and engineers to be trained to do: make broad assumptions about unknowns.
I guess you have to assume that the cities are directly north-south from each other and located in the same time zone in order to get a nice neat answer. And that's something that I want my future scientists and engineers to be trained to do: make broad assumptions about unknowns.
I actually thought it was a rather witty comment, very American. It shows thinking outside the box which is something gained from experential learning, not rote learning. It's the reason Chinese kids do so well on tests, yet they rely on stealing and pirating technology and software and hire foreign design and engineering firms for a lot of their projects. They're smart according to the book, but it comes at the expense of stifled creativity and critical thought.
There are some threads on CD about the "Tiger Mom" phenomonen in the parenting section. One comment I made over there was so what if "Tiger Cubs" know what the Theory of Relativity means at age 10 and can explain it, they're so focused on rote learning that they could never have conceived of it.
I actually thought it was a rather witty comment, very American. It shows thinking outside the box which is something gained from experential learning, not rote learning.
Oh, I agree with stan4. I just though it was funny how a problem was introduced as an example of how American math education is supposedly teh suk when the problem as written cannot be solved.
Oh, I agree with stan4. I just though it was funny how a problem was introduced as an example of how American math education is supposedly teh suk when the problem as written cannot be solved.
I thought it was solved on page 2?
Quote:
Let t be the sunrise
Let Va and Vb be the speed by driver A and B, respectivily
Let x1 and x2 be the distance trvaled by A and B, resppectively when they meet at noon (12).
One equation comes from the total distance travel by both which is the same
(16 - t)Va = (21- t)Vb since both traveled 500 (in fact that 500 number is never used and dosesn't matter in Mile or Km)
Now at noon, each traveled the same time ( t = distance/speed), therefore
x1/Va = x2/Vb, then again each of them completed the remaining distance taking 4 and 9 hours respectively. Incorporating that gives
9Vb/Va = 4Va/Vb
This gives Va/Vb = 3/2 or 1.5
Inserting this on the first equestion gives
t = 6.
Therefore, sunrise was at 6 am.
The OP said this was the correct answer, did I miss something?
The OP said this was the correct answer, did I miss something?
The problem doesn't tell us where the cities are located in relation to one another except for 500 miles. If those 500 miles are on the same line of longitude, then sunrise will occur at the same time in both cities. If they are not, sunrise in city A will occur at a different time than sunrise in city B. And as stan4 pointed out, the problem is silent on the complications that crossing time zones would have on the calculations.
The problem doesn't tell us where the cities are located in relation to one another except for 500 miles. If those 500 miles are on the same line of longitude, then sunrise will occur at the same time in both cities. If they are not, sunrise in city A will occur at a different time than sunrise in city B. And as stan4 pointed out, the problem is silent on the complications that crossing time zones would have on the calculations.
OK, we're all on the same page then. The problem is "solvable" unless you actually think about it for a minute, lol.
OK, we're all on the same page then. The problem is "solvable" unless you actually think about it for a minute, lol.
Yup. Thinking often gets me in trouble, which is why I try to refrain from it as often as possible.
And, actually, I was incorrect about the whole same line of longitude deal because earth's axial tilt messes with that unless you hit either of the equinoxes.
The problem doesn't tell us where the cities are located in relation to one another except for 500 miles. If those 500 miles are on the same line of longitude, then sunrise will occur at the same time in both cities. If they are not, sunrise in city A will occur at a different time than sunrise in city B. And as stan4 pointed out, the problem is silent on the complications that crossing time zones would have on the calculations.
Jeez people, stop thinking too much into it. What is the distance was only 10miles? The answer would still be the same.
Jeez people, stop thinking too much into it. What is the distance was only 10miles? The answer would still be the same.
Did you ever have a problem on a test where the professor gave you all sorts of information and you assumed the question was asking you to find something, so you spent a good 45 minutes on calculations that gave you an answer that you felt good about only to miss it completely because you didn't think too much into it and failed to realize that something else was being asked: something that only took 10 seconds to answer correctly had you only read the question with proper care and attention to detail?
Those kind of test questions, frustrating as they are, teach you something beyond how to set up and solve equations.
I thought it was solved on page 2?
The OP said this was the correct answer, did I miss something?
6-00 it is not correct answer, everyone can check it.
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