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Conics 2014-02-01
From Kassidy:
Hey, I have searched through all the questions about conics and how people use them in the real world, but none of them were very specific on how they are applied and the process, why it's so important etc. I have a project due asking these questions and it's been very difficult finding the right answer, if you could name jobs, how they are use and specifically applied that would be greatly appreciated.
Answered by Penny Nom.
Practical uses of trigonometry 2013-08-06
From tharindu:
use of trigonometry
Answered by Penny Nom.
Practical trigonometry 2009-05-04
From Lori:
I am an ex-math major turned home-schooling parent. I would desperately like to find a word-problem based trigonometry book for my 17-year old son. I don't want graphing or other gobbledy-gook that he'll never use. Does such a thing exist?
Answered by Robert Dawson.
Quadratic equations arising from practical problems 2008-11-24
From Lenval:
Why do quadratic equations arising from practical problems often give physically impossible solutions such as negative distances, negative times or, say, a polygon with a negative number of sides? For example: "A river in flood carries a tree t-squared - 23t metres downstream in t seconds. How long does it take for the tree to be carried 50 metres downstream?" This gives t=25 and t=-2. Please explain the second 'solution', which is not physically possible.
Answered by Chris Fisher and Victoria West.
Practical applications of sequences 2008-01-01
From carl:
can you give me examples of different kinds of practical applications of sequences?
Answered by Penny Nom.
Is there a practical use for radian measure? 2007-10-26
From Paula:
Is there a practical use for radian measure in any profession? Which professions might us radian as opposed to degree measure?
Answered by Harley Weston.
Where do you use trigonometry? 2007-08-21
From jenny:
where do you use trigonometry besides architecture and engineering?
Answered by Stephen La Rocque.
The area of a property 2007-03-14
From Greg:
Hi my name is Greg. I have a piece of property I am trying to buy, but need to find out the square feet of it first. The four sides are unequal lengths and none at a right angle or parallel. Here are the measurement in feet. The base of the square is 29.12 feet in width.
The right side of the square is 44.33 feet high.
The top of the square is 28.80 feet in width.
The left side of the square is 46.20 feet high.
I have not done this math in ages and really need your help.

Answered by Harley Weston.
A fountain as a parabola 2007-03-08
From Emily:
I have to do a math project proving that something in real life is a parabola. I really need some help here because i don't know where to start. I want to do it on a fountain and prove it's a parabola but how do i do that? I would really appreciate it if you could help Emily
Answered by Stephen La Rocque.
Chords and arc lengths 2007-03-08
From Angela:
my dad, who is a welder, asked me a question pertaining to chords and points on an arc to which I cannot for the life of me find an answer or an equation. if you could help, it would be much appreciated. I am sending an attachment of the problem.
Answered by Stephen La Rocque.
A metal shroud for a outdoor fireplace 2007-03-06
From Arnold:
I am making a metal shroud for a outdoor fireplace, it is basically a lampshade type pattern,like the bottom of a cone.The top has to be 6 inches to fit the 6 inch stovepipe,and the bottom will be a 24 inch circle. the sides will be 18 inches in length.With the cost of the sheet metal,I can only afford to cut this out once,can you help me with the pattern ?
Answered by Penny Nom.
A long narrow cone 2007-03-04
From Amy:
I am an art student making a piece of jewelry out of a flat metal sheet. I'm trying to make a long narrow cone that's roughly 3 1/4" long and just slightly under 1" wide at the base. Since I'm no math wiz, I'm having a really hard time. Please help.
Answered by Penny Nom.
Circles 2007-02-22
From Erika:
I have a research paper due on real life uses of conic sections I've looked through all your conic topics and uses of them, but and i cant seem to find real life uses for circles. What are real life uses of circles?
Answered by Penny Nom.
Things that are shaped like a parabola 2007-02-14
From carra:
i can't find other examples of things that are shaped like a parabola except for bridges.............. Pls. help it is due tomorrow. thank you very much:)
Answered by Steve La Rocque, Penny Nom and Walter Whiteley.
An octagonal bird house 2007-01-13
From Soren:
I'm in the process of building a birdhouse that is an octagon (based on previous questions, looks like that's a familiar tune). The essential elements are known, but I get stuck when trying to determine the angle for the cuts that would be made to the thickness of the wood so that they all fit together when assembled. Each octagonal section is 7 inches in width and the peak of the roof will be 2 inches higher than the sides. My sense is that the angle cuts that need to be made to the 'height' of each piece of wood. By height I mean the thinnest part of the wood that is neither the length nor the width to use colloquial terms. While it's clear that a slight angle is needed, it would seem that the angle would necessarily change as the distance from the top of any one side to the peak changes. Please advise if more clarification is needed. The 2 inches is random and can be changed if more convenient. Whew!
Answered by Harley Weston.
Ratios, proportions and medicine 2006-10-25
From Steven:
I don't understand why we need to learn about ratios and proportions because i want to become a doctor and i don't know if i'll ever use this type of math.
Answered by Penny Nom, Claude Tardif and Walter Whiteley.
An octagonal room 2006-10-18
From Rick:
I am a cabinetmaker, and I have a client who has an octagonal room which he would like to be used as a walk-in closet. Each side of the octagon is 60" in length. Each wall section is to have a 24" deep cabinet installed on it. I am trying to figure out the width of each cabinet allowing for a 3" space between cabinets at the front corner.
Answered by Stephen La Rocque.
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.
Why do we bother learning pre-algebra and algebra 1? 2005-12-23
From Priya:
My students always ask "Why do we bother learning pre-algebra and algebra 1?" and I haven't found an answer to satisfy them yet. Can you help me? My students are from grade 9 to 11. I have tried giving them real life examples in each topic but it just feels like they are not satisfied!!!
Answered by Penny Nom.
How is trigonometry applied to everyday life? 2005-12-03
From Yadira:
My question is how is trigonometry applied to everyday lives and functions. Ex: Builders use it but how and what are some examples of the trig-functions or formulas that they use?
Answered by Harley Weston.
Framing an arched wall 2005-08-12
From Mike:
I'm framing a building wall with a curved (arcing) top section. The radius of the section is 74'6" with a height above finish floor of 16'0". The horizontal run of the arced section is 23' 1 1/2" with a low height above finish floor of 12'4". If I start with a 16' stud at the high end how long are the subsequent studs if they are on 16" centers? Short of laying this out on a tennis court how can I work out the lengths of the studs?
Answered by Penny Nom.
A wishing well 2005-03-28
From Don:

I am building a wishing-well out of pieces of 2-by-4. I have included a picture of a miniature version of what I want. There are to be ten 2-by-4 pieces around the well and I want the circle around the outside of the structure to have a diameter of approximately 3 feet. How long to I cut the 2-by-4's to build the wishing-well.


Answered by Harley Weston.
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.
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.
Pi 2004-05-10
From Kim:
I'm a 7th grader at Lakeside Middle School. And I was wondering if you can answer a question for me for my math project. I'm doing a project on pi, and my teacher said to ask an expert like you to ask about how you would use the subject, pi, in real life usage. How would you use pi in real life usage?
Answered by Penny Nom.
Applications of logarithms 2003-09-16
From A student:
I have a project due in my algebra two class dealing with logs and where they are used in life, but I am having trouble finding websites that relate. So I would really appreciate it if you couldhelp me.
Answered by Penny Nom.
The size of a lot 2002-01-26
From Claudia:
I own a piece of property that I need to know the square feet for assessment purposes. The figure they came up with is wrong. They measured from one point to another and halved the sums but that means I own the cul de sac and we don't. My lot is 55 feet wide and one side is 108.96 feet and the other side is 146.04 that extends all the way to a circle. The front of the lot on the cul de sac is stated on the survey like this. 78.21 feet where R=40 feet. This large arc is taken off the size of our land. How many square feet is our lot.
Answered by Harley Weston.
A 3 dimensional 5 pointed star 2001-11-08
From Kent:
I am looking for a formula that will give me a layout for a 3 dimensional 5 pointed star. I want to form it out of sheet metal, using 5 polygons and soldering them at the apex. Can you please help me with this? I would like to be able to give the formula the height of the star from the bottom two points to the top point and also how deep the star is. Thank you very much!
Answered by Judi McDonald.
The law of cosines in the real world 2001-02-21
From Hope:
Do you have any examles and/or labs that show how the law of cosines is used in the real world?
Answered by Harley Weston.
Polynomials and exponents 2001-01-15
From A student:
I am duing a project in math on polynomials and exponents. I need a real life usage of polynomials and exponents for my project.
Answered by Penny Nom.
Parabolas in life 2000-12-03
From Ashley:
I am a student and my teacher recently gave us the assignment of writing a portfolio on parabolas in life and finding examples, three to be in fact, only we have to go into detail about only one. We have been instructed to include such terms as: axis of symmetry, completing the square, parabola, quadratic formula, standard form (vertex form) and vertex. We also must include in our detailed example an equation of the parabola and very specific details, PLEASE HELP!
Answered by Harley Weston.
Bridges and parabolas 2000-11-18
From Lauren:
My name is Lauren, and Im a secondary school student in Ontario. For my gr11 advanced math class I have to find out how and why parabolics are used in arch bridges and write 3 paragraphs on it. People who cohse satelites and whatnot are lucky - I've found a ton of info, but for arch bridges there seems to be nothing.
Answered by Harley Weston.
A roll of paper 2000-01-15
From Richard:
I have a roll of paper, wrapped around a corrugate core, whos diameter is 10.750 in. The outer diameter of the roll is approx. 60 in. The thickness of the paper is .014 in. I am trying to find out how much linear feet of paper is left on the roll, given only the diameter of paper remaining on the core.
Answered by Chris Fisher and Harley Weston.
What are fractals and are they of any practical use? 1996-06-26
From Ron Lewis:
What are fractals and are they of any practical use?
Answered by Chris Fisher.



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