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Ryan, Engineer
Category: Math Homework
Satisfied Customers: 9079
Experience:  B.S. in Civil Engineering
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I'm an English tutor who has been asked to run a maths

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I'm an English tutor who has been asked to run a maths taster session for potential engineering students. I have been asked to teach the learners how to calculate the area of a semi-circular piece of metal which is simple enough.
It's the second part of the session I'm not sure of; which is to outline how to identify and present the cheapest price of three different materials assuming all metals are 10mm thick. I might be overthinking the question but I don't want to make a fool of myself on the day. I've pasted the outline for the lesson below.
… the end of the lesson learners should be able to calculate the surface area of a semi-circular metal plate. Briefly outline how the learner could identify and present the cheapest price from a choice of three different metals for the plate, namely mild steel, aluminium and copper (assume the thickness of the plate is 10mm for each of the alternative metals).’
Submitted: 1 year ago.
Category: Math Homework
Expert:  Ryan replied 1 year ago.


Thank you for using the site. I'll be happy to help you with this. I have a couple of brief questions to ask first though.

1. When you say that this piece of metal is "semi-circular", can you be more specific? It this a flat piece of metal that is a half-circle, like a pizza that has been cut in half? Or is it a curved plate that is the shape of half of a cylinder, like a pipe that has been sliced in half length-wise?

2. How are the prices for the three metals quoted? Are they given in units of money per square centimeter, or in units of money per cubic centimeter?



Customer: replied 1 year ago.
Hi RyanThank you for responding. The outline I've pasted is the exact brief I've been given.I was wondering if the term surface area as opposed to just area suggests the metal is cylindrical. As for choosing the cheapest metals no prices are given just the thickness which is 10mm and the different types of metal. From deduction I would say aluminium is cheaper than brass and brass is cheaper than mild steel but that sounds too simplistic.This is the problem I'm having is the lack of information and our maths tutor is on long term sick.
Expert:  Ryan replied 1 year ago.


Yes, I see what you mean about having limited information.

I would assume that the prices for the metals are quoted as a price per mass (kilograms), or a price per volume (cubic meters or cubic centimeters).

How about if I write up procedures for calculating surface area and volume for both proposed shapes, and then methods for calculating price based on mass and volume. That way you should have all of the bases covered and you can pick and choose which parts to use?

What age group will you be presenting this to (so I can tailor the writing style)?



Customer: replied 1 year ago.
That would be great thank you. The learners are potential engineering apprentices so ages ranging from 16 to19.
Expert:  Ryan replied 1 year ago.

Ok, so around late high school / early college age here in the US. I'll get working on this and will have a Word document posted for you as quickly as I can. You should receive an email notification when the file is posted. Should you have any follow-up questions to ask once you've reviewed the document, please don't hesitate to ask. I'll be happy to explain anything that is not clear.

Expert:  Ryan replied 1 year ago.

Hi again,

Once I got started on this and drew some diagrams, I realized that the "half-cylinder" scenario was unlikely to be needed since no mention was made of any length (or height) of the object. Given the thickness of the semi-circular piece, the only remaining unknown would be the actual diameter, which seems like the simplest interpretation. Should it turn out that you actually need the calculations for a semi-cylindrical object, please let me know and I'll be happy to add that in (no additional charge). I just didn't want to throw too much unnecessary information in here and have it lead to confusion.

Please take a look at the document at the link below and let me know if there is anything that requires clarification:




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