Surface area
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lev888
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How would you calculate the area if you had to paint a rectangular wall that had a rectangular window?
regular area? I would multiply the length and width
lev888
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How would you find the area that needs to be painted, given the dimensions of the wall and the window?
Multiply the wall measurements, add them, then subtract the window/door measurements?
I think that is how it should be done, but the dimensions on the right should be subtracted from 180, hence giving 134 (?)
lev888
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Since my example has only one wall and one window, there is nothing to add. Yes, this is the right approach - calculate the total area of the surface (all walls) and subtract the total area of the "holes" (doors and windows).
Quite frankly, I do not know. It talks about six walls needing paint. And it talks about walls without windows or doors not needing paint. Are there 11 walls. Very badly worded problem.
lev888
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No, only 6 walls. It's the 5 doors and windows that don't need painting.
"walls that did not need painting" means, according to the rules of English grammar, that there were walls that did not need painting. And the windows and door were in THOSE walls according to the text.
It is perfectly possible, and highly desirable, that problems in mathematics be written in grammatical and unambiguous English. The numerate need not be illiterate.
Perhaps it is correct that what was meant was that "a total of six walls needed to be painted, and those six walls together contained a total of three windows and two doors." But that was not said. It is depressing when those who write math text books are only semi-literate. And students have a right to complain when problems are written in confusing English and do not mean what the rules of English grammar strictly imply. Mathematicians, better than almost any other type of academic, know the importance of exact description.
It is perfectly possible, and highly desirable, that problems in mathematics be written in grammatical and unambiguous English. The numerate need not be illiterate.
Perhaps it is correct that what was meant was that "a total of six walls needed to be painted, and those six walls together contained a total of three windows and two doors." But that was not said. It is depressing when those who write math text books are only semi-literate. And students have a right to complain when problems are written in confusing English and do not mean what the rules of English grammar strictly imply. Mathematicians, better than almost any other type of academic, know the importance of exact description.
lev888
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Programmers too.
So it should be "windows and doors in the walls" that didnt need painting, not "windows and doors" in the walls that didnt need painting.
i believe that it should be interpreted that the "windows and doors in the walls" dont need painting, not "windows and doors" in the walls that dont need to be painted.
they definetely should have been more precise
i believe that it should be interpreted that the "windows and doors in the walls" dont need painting, not "windows and doors" in the walls that dont need to be painted.
they definetely should have been more precise
Relative pronouns like "that" refer to the immediately preceding noun. Admittedly, when people are speaking, this rule is frequently ignored, but any resulting ambiguity can be cleared up with questions. In writing, however, a dialogue with the author is not possible. This means that ambiguity must be avoided from the start, and doing so often requires great care with the use of relative pronouns in lengthy sentences.
Obviously, windows never need painting if they are to be transparent, and the doors to a treehouse are usually just holes that cannot be painted. The sentence should have been constructed to say "windows and doors that do not need painted."
"Six walls need to be painted except for three windows and two doors that do not need to be painted."
Writing clear English prose is not impossible, but it takes care.
Indeed.
But I must admit that when I used to have an information technology department reporting to me, their reports and memoranda were often appallingly opaque. When I finished screaming, I would frequently hear, "But I knew what I meant." The only response to that was "Your goal was to make others understand what you meant."
To be fair, the poor programmers (among whom I had worked a long time ago) were tormented incessantly by specifications and revisions to specifications and revisions to revisions of specifications, all of which had apparently been written by chimpanzees