Like even more maths? (WRONG ANSWER REVEALED!)

[ms51ves3]

https://i15.photobucket.com/albums/a376/ms51ves3/DSCF3127.jpg

Once again, put your answer in small text so you don't give it away, and show your working if you can.

[HP]

4.26
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What flavour would you like the windows Harvey?

[ms51ves3]

[trevoriv]

Eighty-twelve?
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Past: '96 Thundercat, '02 ZX636R (A1P), '58 KTM 690 SM LC4 Current: '06 ZX636R (C6F)
Mudskipper wrote: Someone just has to sig that...

[Blue_SV650S]

R=1.7 ... therefore diameter = 3.4
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The purpose of life is to fight maturity.

[ms51ves3]

[ms51ves3]

A clue is you need to use the Quadratic equation

[Blue_SV650S]

[stinkwheel]

Area of floor without cutaways = 12(18+r) = 216 + 12r
Area of central cutaway = πR² = π(2r)² = 4πr²
Area of corner cutaway = 0.5πr²

So cutaways = 4πr² + 0.5πr² = 4.5πr²

Floor area = 200 = 216 + 12r -4.5πr²
-16 = 12r -4.5πr²
-4.5πr² + 12r +16 = 0

Oh how much FUN. You've contrived to make me do a quadratic fucking equation. I last did one of these 17 years ago and I hated them then!

Using the quadratic solving equation: x = -b +or- √(b² - 4ac)/2a
r = -12 - √(144 - (-288π))/-9π
r = -12 - √(144 +288π)/-9π
r = -12 - √1048.779/-28.274
r = (-12 - 32.384)/-28.274
r = -44.384 / -28.274
r = 1.570

Check working:
216 + 12r -4.5πr² = 216 + 18.840 - 34.847 = 199.993

Close enough for government work!


I hate you!
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“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[ms51ves3]

I've not seen the correct answer yet. Keep trying kids

[stinkwheel]

OK. Didn't read the question properly. Drop 1 mark.

Diameter of the central circle = 2R = 2(2r) = 4r

As r = 1.570. Diameter of central circle = 6.28 metres
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Kickstart]

Hi

Total area is 216 including the cutouts.

So

16 = pie * (2 * r)² + 0.5(pie * r²)
32 = 2 * pie * (2 * r)² + (pie * r²)
32/pie = 8 * r² + r²
32/pie = 9 * r²
32 / (9 * pie) = r²
r² = 1.1318
r = 1.064
R = 2.1277

Diameter of central circle is 4.2554

All the best

Keith
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Traxpics, track day and racing photographs - Bimota Forum - Bike performance / thrust graphs for choosing gearing

[Charlie]

Here's how I did it, however I suspect it will be somewhat similar to others.

https://cdn.bikechatforums.com/files/chivesmaths_398.png
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Past: Honda x8rs, Honda City fly, Honda Hornet 250, Honda VFR750, Yamaha xt600e.
Current: Honda CBR929RR & Yamaha XT660Z Tenere

[stinkwheel]

Keith.

Your first proposition is incorrect. The overall length of the room is not 18.0m.
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[Charlie]

I made the same mistake as Keith when I first did it, only checking the diagram after did I realise.
____________________
Past: Honda x8rs, Honda City fly, Honda Hornet 250, Honda VFR750, Yamaha xt600e.
Current: Honda CBR929RR & Yamaha XT660Z Tenere

[ms51ves3]

Does anyone want me to post up my working and answer yet?

[Blue_SV650S]

[stinkwheel]

[ms51ves3]

Stink, your answer wasn't correct. No ones has been correct so far.

[stinkwheel]

[The Original Muzza]

I got the same as Blue (3.14 radius for R).
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Current Bikes: Husqvarna Svartpilen 401 (2020)
Former Bikes: Honda MSX125 (2014), BMW Funduro (1996), Honda VT500 (1983), Yamaha FZR250 (1989), Suzuki GZ125 Marauder(2005),:Triumph TT600 (2002) (stolen)
From then on, I and the bicycle feelings deeper.

[ms51ves3]

[stinkwheel]

Shitstorm incoming in 5, 4, 3, 2...
____________________
“Rule one: Always stick around for one more drink. That's when things happen. That's when you find out everything you want to know.”
I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[HP]

dont post thr answer im going to retry it as i read the diagram wrong last time
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What flavour would you like the windows Harvey?

[ms51ves3]

Click me for the answer.