calculator that works out area?

Soldato
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Is there a calculator that works out areas etc?

Reason i ask is, i am re-sitting GCSE Math and as i am knocking on 40, i am really struggling with the formulas ie working out areas of circles, diameters, triangles, trapeziums etc!!
 
Is there a calculator that works out areas etc?

Reason i ask is, i am re-sitting GCSE Math and as i am knocking on 40, i am really struggling with the formulas ie working out areas of circles, diameters, triangles, trapeziums etc!!

Pretty sure this kind of calculator would be forbidden in the exams.

Practice makes perfect. ;)
 
I think it would be easier to just learn the formula - I know it might be hard, but once you get it you'll be fine - also, you'll want to show working in the exam.

triangle - just 0.5*length*width
circle - pi*r^2
etc... just get them learnt, may seem hard, but it's worth knowing them, and once you get it, it'll be simple.
 
i know learning them is the correct way, but i'm looking for the easiest!!

It is a weeks intense revision and the following Monday and Tuesday you sit the exams!!

I was given some workbooks for pre-week course and it has reminded me of how much i don't know!!
 
I don't understand how any calculator could produce the result you require without mind-reading, or some kind of advanced calculator that can read the exam question from the paper. You are going to have to know what numbers to put into the thing, so therefore you should know what calculation it is doing?
 
I don't understand how any calculator could produce the result you require without mind-reading, or some kind of advanced calculator that can read the exam question from the paper. You are going to have to know what numbers to put into the thing, so therefore you should know what calculation it is doing?

I think he was hoping for a option for "trapezoid/circle/sqaure"" and it would ask him for each measurement :p
 
An area is measured in something like cm2, so will always be two lengths multiplied together then times a simple number.

For a rectangle or a square, you just multiply the two lengths together.

For a triangle, it can always be considered as half a rectangle. Or rearranged into half a rectangle. So here the problem is working out which two distances you use, I'm fairly confident it's always the longest side times the distance from that side to the opposite corner, halved.

Circles are a bit smaller than a square. If you imagine a square with a circle inscribed you see that it's the diameter, times the diameter, then a bit smaller as the "corners" are rounded off. It turns out to be half the diameter, times half the diameter, times 3.14. If it actually was a square you'd be multiplying by four, but it's a bit smaller.

Trapeziums are nearly the same as rectangles. You multiply the average of the two parallel lengths by the distance between them. It'll look something like a.0.5.(b+c).

Most other shapes are dealt with by drawing arbitrary lines to break the complicated shape, which you don't know a formula for, into simple ones which you do. You could turn the trapezium into a rectangle and two triangles for example.

You don't need (or want) a calculator for this, just some time drawing pictures :)
 
I guess this magic calculating device could ask for the distance between A and B and calculate the answer.. .wait what so the operator needs to know what the exact name for distance AB is? Is it radius. Or cirumference? Or maybe it's a chord. Who knows. I bet he magic calculating device does. This is almost like having a calculator with a preset 'times table' press this button for 4x5. Press this button for the answer to 6x8. Oh wait....
 
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