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math beyond school pythagoras

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35 items are filed under this topic.
A barn roof 2016-05-29
From Joe:
Is it possible to build a barn roof (irregular pentagon?) with a 12' base and the other 4 sides 4' each? Thanks.
Answered by Penny Nom.
A deck that is half an ellipse 2016-02-28
From Steve:
On your website, I was reading a question and your response from a girl named Angela in which you provided a formula by which her father, a welder, could figure out points on an arc corresponding to equal 3' intervals on a 30' chord where the vertex was 1' off the chord. Is there an equivalent formula when working with an ellipse? I suspect this change will make the calculations significantly more complex. I am building a deck that is half an oval, and would like to be able to mark out the perimeter by measuring the distance from regular intervals on the primary access to a corresponding point on the perimeter. I will then connect the points on the perimeter and cut a reasonably smooth arc. The length of the primary access will be 22' and width of the deck at the vertex is 9'. I would like to be able to know the distance from the primary axis to a point on the perimeter at equal intervals of 6" along the primary axis. Can you help?
Answered by Penny Nom.
Covering a 12 inch by 12 inch square hole 2014-07-02
From Patricia:
I am putting in a new bathroom fan. I am wondering if a new light with a 15 inch diameter will cover the existing square hole which is 12 by 12 inches? If the existing hole is 11 1/2 by 11 1/2 inches?

Also, if the 15 inch diameter does not cover the 12 by 12 hole, what size diameter would?

Thank you.

Answered by Penny Nom.
The fourth side of a quadrilateral 2014-01-23
From joanna:
left vertical measurement 2560mm
right vertical measurement 1850mm
base horizontal measurement 1750mm
question - what will the 4th measurement be please.
using a scale drawing I make it approx 1900mm but require an accurate measurement



Answered by Penny Nom.
A square inscribed in a circle 2013-10-14
From Jenn:
Hello! I am about to buy a 7'9" round rug, but I want to have it cut down into a square. What's the largest square I can obtain from this? Thank you!
Answered by Penny Nom.
Milling round stock to square stock 2012-12-17
From Bryan:
Question from Bryan:
I want to know what the smallest diameter round is that will make a 3-1/4" square? Is there a formula for that? I am milling round stock into square.
Thank you.

Answered by Harley Weston.
Calibrating a conical tank 2011-02-05
From Bill:
Hi, I have a round tank with tapered sides where I know the diameter at the top and bottom. Is there a formula I can use to calculate the volume by measuring from the bottom up the side (at the angle of the side) to any given point? Thanks, Bill
Answered by Stephen La Rocque and Penny Nom.
Constructing a tipi 2010-09-20
From mike:
we are thinking about making a lightweight tipi tent but we need to know what the angles and lengths of each side that we will need to cut. The height of the tipi wants to be about 2.2m span at the widest point wants to be about 3.2m we want to make it based upon a 6 sided(hexagon) shape thanks for your help
Answered by Harley Weston.
A play tent 2010-06-28
From Susan:
Hi!!! I am making a play tent as seen at the link below and need to figure out how to get the dimensions for the cone shape. The one shown has 4 different seams, but I guess I can get away with just one seam to sew it together (?) I need it to go over a hula hoop as that is what I am using for the round support at the top. My hula hoop is 35" in diameter from outside edge to outside edge. I would like the height of the teepee to be around 30" from the center to the peak. Thanks so much, oh my gosh, I have been fretting for 2 days about this and my hair is about to fall out!!!! Please contact me if you need any additional info.


Answered by Penny Nom.
The low leg height of a shutter 2010-05-20
From brian:
I work for a shutter company and am in need of a formula to figure out what the low leg height would be if given the width of shutter, the high point of arch top and the radius. example would be a 18" wide shutter with a 80" high leg on the right side and a 30" radius. I would need a way to figure what the low leg height (left side of shutter) would be. Or if given width, low leg height and radius what the high side would be? If any of this can be given in laymen's terms it would be much appreciated. Thanks, Brian
Answered by Harley Weston.
A square corner 2010-02-11
From Trevor:
I am building a new house and wish to set it out on site with the use of profile boards and string. I want to be certain it is correct in terms of squareness. I have a vague idea that the square on the hypotenuse should be equal to the sum of the squares of the other two sides.

I get a little lost here and need some help. The building is a rectangle measuring 40x30 feet to exterior brickwork. I guess that the length of the hypotenuse should be exactly the square root of the combined squares of the two sides.

Using the above measurements could you give me calculations from nuts to soup as to the correct length of the diagonal. And what adjustments are needed if everthing is not in accord.


Answered by Robert Dawson.
Loading a headboard in a uhaul 2010-01-20
From gina:
I have a uhaul 9'10" long 4"9"wide 4'7"height I have a headboard 74 inches in height would it fit the box diagonally
Answered by Penny Nom.
Segments of a ring gasket 2009-09-20
From Robert:
I am in the process of making an Excel spreadsheet in which our sales team just needs to enter the outside diameter, inside diameter, and number of segments to price ring gaskets that are too big to fit on a sheet of material and need to be cut into segments. With your help I was able to create a spread sheet that can calculate the Chord lengths, and Segment height on a single gasket segment. I am now stuck trying to come up with a formula to figure out the height of the second segment when it is stacked on the first segment, then use it to add more depending on the quantity of segments needed. I have an illustration below showing 2 segments (of a gasket that was segmented into 4 pieces) stacked together. I need to find a formula to get the dimension from "A" to "B".
Answered by Harley Weston.
A paper towel roll 2009-08-19
From Jeff:
I am making a spiral tube with paper that is 2" in dia. and 102" long I will be using paper that is slit 3" wide how many lineal feet of paper will I need to to cover the 102" I will be using 3 rolls of paper that will over lap the other by half to make a hard tube (paper core) in a roll of paper towels Thanks Jeff
Answered by Penny Nom.
Octagonal panels for a horse pen 2009-03-25
From Tony:
I am building a pen for my horse. I am going to use 12' panels in the shape of an octagon. How many feet will he have from side to side using 12' panels.

Answered by Robert Dawson and Penny Nom.
An octagonal landscaping frame 2009-03-01
From Richard:
Hi I am trying to put landscape timbers down in octagon shape that measures 6 feet across and outside measures 360 degrees.. The timbers are 4 inches by 4 inches. I need to know at what angle to cut boards and at what length i need to complete octagon.
Thanking you in advance for your kind assistance.
Richard :)

Answered by Harley Weston.
The floor area in a spherical space station 2009-02-14
From Ed:
I am writing a science fiction novel that involves a spherical space station with a radius of 800 meters. Inside, artificial gravity allows parallel floors set 4 meters apart. If you count the floor that has a radius of 800 meters as Floor 0, then the next floor up (Floor +1) would by 4 meters above the surface of Floor 0. There would then be Floor -1 4 meters down from Floor 0. This would continue until you reach the top or bottom floor, where there is at least 4 meters but less than 8 meters to the top or bottom of the sphere. Obviously the top and bottom floors would have the (same) smallest area, while Floor 0 would have about 2 million square feet.

My problem is figuring out the total area of all of the floors, or for that matter, any particular floors or the total number of floors (the total of all the + floors, the - floors (these numbers will be the same) plus Floor 0.


Answered by Penny Nom.
Out of school applications of Pythagoras Theorem 2008-01-23
From Laura:
Hi, I am currently working on a math summative in which I have to choose a real life subject and relate it back to the material in my grade 12 math class. I find the history and discovery behind the Pythagorean Theorem and Identity very interesting, but I have yet to find a real-life application of the equations. Yes, I know they are used for finding distances, heights etc., but realistically, how many people actually use it in those situations? Very few. I was hoping for a new application. Is the pythagorean theorem (sin^2x + cos^2x = 1) even applicable? Thank you, Laura
Answered by Harley Weston.
Building a garage 2007-07-29
From charles:
I want to build a garage that is 24 feet 4 inches wide by 50 feet long. can you please tell me what the length of one corner is to the other?
Answered by Penny Nom.
Pythagoras theorem in daily life 2007-07-17
From sana:
i would like to what are the 5 practical uses of the Pythagoras theorem in daily life??? its for a math project thanx a lot sana
Answered by Penny Nom.
I need to cut an octagon 2006-09-23
From Freddie:
I have a 48 inch square piece of wood that I need to cut into an octagon, help. What's an easy way to just measure and cut it.
Answered by Penny Nom.
Designing a garage 2006-06-08
From A builder:
I'm currently designing a garage and came upon this interesting math problem. I've tried using various methods to solve it but have so far been unsuccessful. I've included a picture as its far easier to show you my question than explain it verbally. I realize it could be done by trial and error but i'm looking for a real solution.
Answered by Stephen La Rocque and Penny Nom.
The area of a block of land 2006-03-26
From Ronald:

I have a building block of land with four unequal sides and only one right angle. I want to know the total area (in metres) and how the calculations were carried out.

The four sides are: Rear of property: 9.14 metres
left side: 36.9 metres
Right side: 32.61 Metres
front to street: 27.43 Metres

The front to street and right side constitute a right angle. but there are no others.

Answered by Penny Nom.
An irregular octagon 2006-01-20
From Robert:
I am building a poker table which is in the shape of an irregular octagon. I know the table measures 72 inches long and 48 inches wide with two parallel straight sides of equal length and six smaller sides of equal length ( three at each end of the table), what I don't know are the lengths of the any of the sides.
Answered by Harley Weston.
The area of an octagon 2006-01-03
From Nikki:
I want to figure out the square footage of an octagon. i have 8 panels that are 24" wide. Its for my dogs and i wanna know how much room they'll have.
Answered by Penny Nom.
The sides of an octagon 2005-11-02
From Royce:
I understand there is a simple calculation to determine the sides of an octagon when you know the distance across the parallel flats. something like .447 . can you help?
Answered by Penny Nom.
Practical applications: parabolas and Pythagoras 2004-10-24
From Connie:
Provide two examples of real life objects that incorporate parabolic shapes. Explain the reason why the parabolic shape was used in each object.

I need at least one practical application of the Pythagorean Theorem.

Answered by Penny Nom.
Pythagoras in everyday life 2004-10-13
From Tiffany:
I was wondering if you have any real-life uses of the pythagorean theorem that you use in your everyday life.
Answered by Penny Nom.
The area of a lot 2004-09-29
From Deb:
I am trying to figure out how many square feet are in a piece of property. Start at Point A-then go 140 feet north-then 100 feet due east-then 300 feet at an angle southeast so that connecting to point A would be a straight line (right angle to first line north.)
Answered by Penny Nom.
An Octagonal playhouse 2004-07-13
From Levi:
I'm building an octagon playhouse for my son that is 8 feet wide. what would be the measurements of each of the eight sides.
Answered by Harley Weston.
A stained glass window 2004-03-29
From Kay:
I'm doing a stain glass project and it's on a 4 foot across octagonal window...and I'm trying to set up the pattern and I don't know how long the sides are!
Answered by Penny Nom.
Bundles of asphalt shingles 2004-01-24
From Larry:
According to my study material 4:12 multiplying factor for shingles is 1.054. The question reads as follows: A building with a floor plan of 3350 sq. ft. and a roof slope of 4:12 will require _______ bundles of standard asphalt shingles.
Answered by Harley Weston.
A triangle and a circle 2003-03-21
From Jynks:
We need a formula that we can use to figure this out for work. We aren't math wiz's or students. Basically we know 3 points in space of a triangle, we know the length of each side and the length of the line from apex to base line. Each point of the base line ends upon the circumference of a circle. IS three a way to work out the radius of that circle.
Answered by Penny Nom.
The pythagorean theorem in everyday life 2001-01-06
From Josh:
What are some ways that we use the pythagorean theorem in jobs, or even in everyday life?
Answered by Claude tardif.
An application of Pythagoras' theorem 1996-04-09
From Mike Jones:
We'd like to know what practical applications there may be for the Pythagorean theorem.
Answered by Penny Nom and Maxine Stinka.



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