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Tricks 'n' Tips


SidAndBob

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For those who don't know what BODMAS is:

 

BO - Brackets off (work out the contents of the brackets first).

D - Division is the next highest priority

M - Multiplication is next on the list

A - Addition

S - Subraction

 

It's always best to write things using brackets to show in which order to do stuff because whilst (A+B/C) always means A+(B/C) it can be interpreted in the wrong way by someone who doesn't understand BODMAS.

Edited by studlyone
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For those who don't know what BODMAS is:

 

BO - Brackets off (work out the contents of the brackets first).

D - Division is the next highest priority

M - Multiplication is next on the list

A - Addition

S - Subraction

 

It's always best to write things using brackets to show in which order to do stuff because whilst (A+B/C) always means A+(B/C) it can be interpreted in the wrong way by someone who doesn't understand BODMAS.

 

So now everyone who reads this will know the correct sequence, but...

What about those Caches that have already been set by people who didn't know BODMAS?

What about those that have yet to be set by people that haven't read this so may not know BODMAS?

What about those that have a bad day and forget their BODMAS in the excitement of finding the last number of the sequence? :P

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Make the maths clear, too. Not forgetting BODMAS, people have different interpretations.

 

(A+B/C) could mean either A+(B/C) or (A+:blink:/C.

 

Oh.... have some anti-bacterial gel close by.

 

No. (A+B/C) always means A+(B/C), and it's not at all ambiguous.

 

Multiplication and division takes precedence over addition and subtraction. Bodmas is right.

 

But unless you knew that multiplication and division takes precedence it is ambiguous....

 

Anything's ambiguous if you don't have the knowledge. When I were a lad, the precedence of multiplication and division was taught in my old Primary School, so surely it can be assumed that people know this?

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For those who don't know what BODMAS is:

 

BO - Brackets off (work out the contents of the brackets first).

D - Division is the next highest priority

M - Multiplication is next on the list

A - Addition

S - Subraction

 

It's always best to write things using brackets to show in which order to do stuff because whilst (A+B/C) always means A+(B/C) it can be interpreted in the wrong way by someone who doesn't understand BODMAS.

 

I always though the "O" in BODMAS stood for order as in 2^4 (2 to the power 4), for example, would follow the brackets, then would come division, etc.

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For those who don't know what BODMAS is:

 

BO - Brackets off (work out the contents of the brackets first).

D - Division is the next highest priority

M - Multiplication is next on the list

A - Addition

S - Subraction

 

It's always best to write things using brackets to show in which order to do stuff because whilst (A+B/C) always means A+(B/C) it can be interpreted in the wrong way by someone who doesn't understand BODMAS.

 

I always though the "O" in BODMAS stood for order as in 2^4 (2 to the power 4), for example, would follow the brackets, then would come division, etc.

It indeedy do is. e.g.

 

Explain the answer that a calculator would give to the calculation 4 + 70/10 x (1 + 2)²- 1 according to the BODMAS rules.

 

Brackets gives 4 + 70/10 x (3)² - 1

 

Order gives 4 + 70/10 x 9 - 1

 

Division gives 4 + 7 x 9 - 1

 

Multiplication gives 4 + 63 - 1

 

Addition gives 67 - 1

 

Subtraction gives 66

 

Edited to put a couple of ²'s in, instead of the 2's and thus not to appear to be a wally :)

Edited by jerryo
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I'd never heard of BOSMAS until reading this thread, and I took A Level maths not 10 years ago. I think if people are going to make such in-depth equations they need to make it clear to everyone (including those without good mathematical knowledge) how the equation should be solved. Maybe some kind of check-sum should be included.

If there is any chance of ambiguity people should encourage cachers to contact the owner before attempting it. (Unless of course a quick check proves the 'other' solution to be unrealistic/impossible etc.

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I'd never heard of BOSMAS until reading this thread, and I took A Level maths not 10 years ago. I think if people are going to make such in-depth equations they need to make it clear to everyone (including those without good mathematical knowledge) how the equation should be solved. Maybe some kind of check-sum should be included.

If there is any chance of ambiguity people should encourage cachers to contact the owner before attempting it. (Unless of course a quick check proves the 'other' solution to be unrealistic/impossible etc.

 

This is a double edged problem in that old f***s like myself automatically use BODMAS whereas younger folks probably work from left to right. When I see caches using brackets, etc I usually contact the cache owner to determine which method has been used as the difference can be large. I think Bambography has a good point here in that a checksum should be included. Geochecker is also a good resource but not much use when you are in the cache vicinity and you do not have access, by any means, to it.

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I'd never heard of BOSMAS until reading this thread, and I took A Level maths not 10 years ago. I think if people are going to make such in-depth equations they need to make it clear to everyone (including those without good mathematical knowledge) how the equation should be solved. Maybe some kind of check-sum should be included.

If there is any chance of ambiguity people should encourage cachers to contact the owner before attempting it. (Unless of course a quick check proves the 'other' solution to be unrealistic/impossible etc.

 

Maybe it was just a Wales syllabus thing but my maths is only GCSE and I was only in second group. So highest grade I could ever achieve was a C. But we covered BODMAS.

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Explain the answer that a calculator would give to the calculation 4 + 70/10 x (1 + 2)2 - 1 according to the BODMAS rules.

 

Brackets gives 4 + 70/10 x (3)2 - 1

 

Order gives 4 + 70/10 x 9 - 1

 

Division gives 4 + 7 x 9 - 1

 

Multiplication gives 4 + 63 - 1

 

Addition gives 67 - 1

 

Subtraction gives 66

It's early (for me) and I'm probably about to make a fool of myself but where did the 9 in the Order line come from?

 

edit to say is (3)2 the same as 3 to the power of 2? I've never seen it written that way before if it is :)

Edited by dino-irl
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It's early (for me) and I'm probably about to make a fool of myself but where did the 9 in the Order line come from?

 

edit to say is (3)2 the same as 3 to the power of 2? I've never seen it written that way before if it is :)

It's obviously early for me too as I tried to get the 2 as a superscript and failed. That's what you get for being a smart@rse and copying something from the Interweb without thinking about it. I have a maths qualification so I'll forgive myself. Sorry, though! :P

 

Actually when I started caching, because of said maths interest, I would try to calculate coords like 54°45.(p)(q)(a) as 54°45.pxqxa as the brackets in maths mean multiply. I agree that there should be a checksum too. But it won't happen. :)

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We're all for a checksum, and applaude those that take the time to add it, same goes for geochecker.com link where the info can be worked out and checked before you set out.

 

Should there be something in the guidelines somewhere or perhaps a prompt on the page where the cache data is uploaded?

 

Don't mind either, horses for courses, but if we are travelling a distance for a cache it does give confidence that a find is on the cards.

 

H&L

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I'd never heard of BOSMAS until reading this thread, and I took A Level maths not 10 years ago.

 

Blimey, you'll be telling me you don't know SOH-CAH-TOA next. (Not what you do to your feet after a long walk, as my incredibly funny and witty maths teacher used to say).

 

Anyway, although we didn't all have ancient maths teachers to teach us ancient maths, in this techy age users of Excel and programmers should at least have some grasp of operator precedence.

 

For example in Excel =4+70*(1+2)^2/10-1

 

Gives 66 as predicted above.

 

Editied so I dont look a complete fool

Edited by Team Sieni
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Blimey, you'll be telling me you don't know SOH-CAH-TOA next. (Not what you do to your feet after a long walk, as my incredibly funny and witty maths teacher used to say).

 

My maths teacher taught us "Some Officers Have Carts And Horses To Order About" to remember this one - still can remember 40 years later but I do use it most days! For those to whom this means nothing:

 

Sine = Opposite/Hypotenuse

Cosine = Adjacent/Hypotenuse

Tangent = Opposite/Adjacent

 

I'm struggling now to see how this is a tip or trick but a couple of my caches require this knowledge!

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I have two simple methods for solving caches with maths problems:

 

1. Use a calculator (though I do recall a cheap calculator I had many years ago which didn't apply BODMAS and so got the answer wrong ;) ).

 

2. Get Steph to do it ;)

 

There's a cache near us which we did a while ago where the owner has clearly got the answer wrong for the reasons discussed here. Fortunately it was obvious which was the correct answer. We pointed out the error to the owner and...

 

it's still wrong.

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For those who don't know what BODMAS is:

 

BO - Brackets off (work out the contents of the brackets first).

D - Division is the next highest priority

M - Multiplication is next on the list

A - Addition

S - Subraction

 

It's always best to write things using brackets to show in which order to do stuff because whilst (A+B/C) always means A+(B/C) it can be interpreted in the wrong way by someone who doesn't understand BODMAS.

 

I always though the "O" in BODMAS stood for order as in 2^4 (2 to the power 4), for example, would follow the brackets, then would come division, etc.

 

Eldest RTB has just done this at school (year 7, just started secondary) and they have the O as Other. It therefore includes powers, trig functions etc. Confused me as I was taught it stood for Of

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My tip.

 

If you have just bought a vist HCX like me. DONT (while driving out to do some caching) decide to clear your tracklogs..... click select all (because you cant be bothered to read all the options)......click delete.

 

for some reason this clears all the waypoints off your GPS leaving you feeling depressed and directionless. Took me ages to enter all the coords for the caches by hand on the road. :o

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My tip.

 

If you have just bought a vist HCX like me. DONT (while driving out to do some caching) decide to clear your tracklogs..... click select all (because you cant be bothered to read all the options)......click delete.

 

for some reason this clears all the waypoints off your GPS leaving you feeling depressed and directionless. Took me ages to enter all the coords for the caches by hand on the road. :D

You should look into my tip about uploading the POI for all caches if the Vista HCX supports it. It would have bypassed this problem.

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