The reason the teacher gets 15 as the answer is because she's using cross multiplication. I remember this because one of the first things I said when learning math was, "pfftt, when am I ever going to need this stuff in life?" And believe it or not this basic procedure has helped me out lots of times. It goes like this: -- If it takes 10 minutes to yield 2 pieces, how much time would it take to yield 3 pieces? So 2/10 = 3/x Cross multiply and you get: 30 = 2x And of course 1x = 15. Now don't ask me which answer is right because somehow they both make sense. It's a poorly worded problem, definitely.
I don't think it's poorly worded. It's pretty clear it should be 20 minutes. It's a trick question and the teacher got tricked.
agreed. I have no idea how anyone could argue that the answer could be 15. even if they know what she meant, that's not what the question actually asks...
Good pont, but she can still saw off a even thinner slice (like a 1/8 inch thin slice) and then break that in half.
Swoly went over the algebra of what the question was trying to ask on the first page. This is not cross multiplication- no fractions or percentage involved. It just so happens that your scenario works with the numbers given.
Now that I think we've all reached a consensus that the answer is indeed 20, I say we move onto more important matters like "What does Marie look like?" Now, I think it's safe to say that if it took Marie 10 minutes to saw a board with that non-serrated POS saw she was using, my only assumption can be that she looks like this : Sexy lumberjacks FTW!
You can use cross multiplication, but not the way you set it up. It should be: the number of cuts over the number of minutes, so that 1/10 = cuts/x since, pieces = cuts + 1, then cuts = pieces - 1 1/10 = (pieces - 1)/x 1/10 = (3 - 1)/x 1/10 = 2/x The rate of 1 cut per 10 minutes does allow for the application of cross multiplication.
The only way the answer could be 15 minutes is if the question said that the board was attached to a wall. The dingleberry teacher doesn't realize is that it only takes 1 cut to create 2 pieces of wood. We know that it is 10 minutes per cut. It takes 2 cuts to create 3 pieces of wood. 2 cuts x 10 minutes/cut = 20 minutes. Must be from the Sarah Palin school of math.
Certainly that was not what was asked in a simple math question. Teacher simply has it wrong. Now, that reminds me...who could that math teacher be? Do we have any math teachers who usually get it wrong on this board?
Alternatively, it's impossible to cut a board into 3 pieces with a single saw. Once you cut it once, it becomes 2 distinct boards. The original board no longer exists.
The wording is very confusing. If she is cutting a board into 3 pieces at that rate, it should take 15 minutes, I think. Wait, what?
it's a trick question. 1 cut take 10 minutes. And 1 cut equals 2 pieces. Now, if she is going to make three pieces, she would have to add one more cut, which takes 10 mins. So 2 cuts equals 3 pieces. 10+10=20
Exactly. And the teacher got tricked. OP, please print out this thread, go back to the teacher, let him/her read it, then report back. At least the teacher knows that there are other people out there who do not get it.
Probably a Muslim or a black guy. One of those people who are trying to destroy the freedom we have in the West. Most likely a black Muslim.
Keep trying. Hey, you got applause from ASidd1990. Maybe he will rep you again. You got a chuckle the first time around. It gets lamer every time you do it...probably that's why you added the "black" part .
