Math is hard

mrblaine

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I'm ordering a chimney chase cover. I'm using their form. It states to add 1/2" to the actual hole diameter for the existing flue pipe size so the new collar will fit over it. My hole size is 15". That means I should use 15 1/2". No problem.

Then it says to add 1/4" to the actual dimensions of the chase so the flanges will drop down over it. No problem.

The difficulty lies in the last bit of instructions. https://www.rockfordchimneysupply.com/chimney-chase-covers/stainless-steel-chase-covers

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I explained to the tech that if you follow the diagram and notes, you are making the hole size 1" smaller for every 1/2" you add to each side locating dimension. He insisted it was making the hole bigger. No, it will be smaller. Not sure how that part of math is so hard.
 
That is really silly.

I really sometimes wonder how folks like that tech get by with their daily lives.
 
the way I read it was that the 1/2" was added specifically to the hole diameter, not to the locating dimensions.

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If I was trying to order it, my confusion would be whether to provide the locating dimensions as-measured, or what they would be with 1/2" added to the hole diameter and 1/4" added to the chase dimensions. We're probably seeing the same problem from two different angles, but I agree there's some things that don't add up.
 
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the way I read it was that the 1/2" was added specifically to the hole diameter, not to the locating dimensions.

View attachment 395171

If I was trying to order it, my confusion would be whether to provide the locating dimensions as-measured, or what they would be with 1/2" added to the hole diameter and 1/4" added to the chase dimensions. We're probably seeing the same problem from two different angles, but I agree there's some things that don't add up.

Look at the part I circled that is in their instructions. Yes, they want you to add 1/2" to the hole diameter. That effectively moves the sides of the hole 1/4" closer to each of the 4 sides of the cap. Then to locate the hole in the rectangle, they want a number from the edge of the hole at the largest part over to the edge of the cap. They want that at all 4 sides per their diagram. That is what "each" hole dimension refers to.
 
I read it as an extra half inch to each hole diameter (dimension) as there are options for more than one hole. I don’t believe they are referring to the hole locations. It is not as clear as it could be and can certainly be interpreted in different ways.
 
I read it as an extra half inch to each hole diameter (dimension) as there are options for more than one hole. I don’t believe they are referring to the hole locations. It is not as clear as it could be and can certainly be interpreted in different ways.

And if that were the case, when I had the certified tech on the phone who exactly knows what we were ordering, that was his opportunity to clarify that is for each hole if there are multiple holes and not for the hole location dimensions.
 
I'm seeing it like freedom_in_4lo and taylormade73.

What I'm not understanding is why aren't the dimensions that locate the hole(s) based on the center of each hole?

Come to think of it, I guess "hole to hole" ain't a thing either, so even more questionable math is required.
 
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I'm seeing it like freedom_in_4lo and taylormade73.

What I'm not understanding is why aren't the dimensions that locate the hole(s) based on the center of each hole?

Come to think of it, I guess "hole to hole" ain't a thing either, so even more questionable math is required.

A lot of stuff is measured in place on an existing cover. It is easier to measure from the edges to each side of the pipe rather than pull the flue cap, get the diameter of the pipe, calculate the center and then do that above the edges of the chase cap since most of them stick up a few to several inches. I know how to find the center of it using a long enough straight edge and a couple of framing squares run over against the sides of the pipe. Not everyone may figure that out.
 
Let's do some common core math.

I've never been a fan. But, after studying it some, (very casually) what I believe they are doing is trying, poorly, to teach folks how to do math the way most of us do it in our heads anyway. If someone tells you that you can buy 32 items at 16 dollars each, most of us break it down to 30 x 16 + 2 x 16 so we have an idea of the total. 30 x 16 is 3 x 160 or 480 + 32. Take 20 from 32, that makes it 500 + 12 or 512.

Or at least that is what my cursory look at what they are doing tells me.
 
I've never been a fan. But, after studying it some, (very casually) what I believe they are doing is trying, poorly, to teach folks how to do math the way most of us do it in our heads anyway. If someone tells you that you can buy 32 items at 16 dollars each, most of us break it down to 30 x 16 + 2 x 16 so we have an idea of the total. 30 x 16 is 3 x 160 or 480 + 32. Take 20 from 32, that makes it 500 + 12 or 512.

Or at least that is what my cursory look at what they are doing tells me.

I agree with you 100%. This is what I have surmised as well. However, as you said, they’re teaching it in a very poor way. We have two kids in school right now and even with lots of explanation they are both struggling with it. When I teach them the way we learned (carry the 1) they understand much better.

Every parent I know has the same grievances, that their kids are struggling so much with the common core and they’re falling behind because of it. I talk to the teachers and they all hate it.

Everyone is in agreement (teachers and parents that I speak to at least) that what they’re trying to teach is good, but the way they’ve gone about it is lackluster at best.
 
That's how one ESTIMATES. Round to something easy, then comp it a bit in the head. If you want the exact answer, grab a piece of paper & pencil - or preferably, a calculator!
 
I've never been a fan. But, after studying it some, (very casually) what I believe they are doing is trying, poorly, to teach folks how to do math the way most of us do it in our heads anyway. If someone tells you that you can buy 32 items at 16 dollars each, most of us break it down to 30 x 16 + 2 x 16 so we have an idea of the total. 30 x 16 is 3 x 160 or 480 + 32. Take 20 from 32, that makes it 500 + 12 or 512.

Or at least that is what my cursory look at what they are doing tells me.

Same. First time somebody was trash talking it and showed me how it works I said...That's how I do it in my head.

I'm not a psychologist or a neuroscientist so I don't know if we lose anything by not learning it the way we did in the early 90s, but to be frank, I barely remember doing that stuff. I struggled the last time I had to show somebody long division, and I don't remember the process for multiplying multi-digit numbers on paper at all. It's funny because I do trig, calculus, and linear algebra and convert between decimal, binary, and hex on a daily basis but I can't remember, let alone teach, how I learned to multiply on paper the way I did in when I was 9. I handle it in my head the way you describe as long as there's at least one number with no more than 2 significant digits, after that I pull out a calculator.
 
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