## Simple Machines B/Compound Machines C

Unome
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### Re: Simple Machines B/Compound Machines C

JonB wrote:
DannyTheAwesome wrote:Did you compete in nationals last year?
Yes.
I wish I did but I took the Simple Machines Nationals test on Saturday.
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### Re: Simple Machines B/Compound Machines C

Unome wrote:
retired1 wrote:Measured from the fulcrum, distance left times weight = distance right times that weight. Or d1wt 1 = d2 wt2 or wt1/wt2 = d2/d1 There is your ratio. They are labeled wt A, B, and C: the way you assign the weight letters, it is either the ratio above or the inverse of it. Say the distances are 50 for A and 30 for B. The ratio of A/B would be A/B = 30/50 or simplified = 3/5 If the ratio was B/A it would be 50/30 or 5/3
Yeah, that's a better explanation than mine.

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### Re: Simple Machines B/Compound Machines C

Coach here... The two distances are rarely whole numbers. So when the students provide their ratios, should they provide fractions or should they resolve the fractions?

As an example, let's say dA is 18.4 cm and dB is is 5.3 cm. Should their answer for the ratio A/B be 5.3/18.4? Or should they go ahead and resolve the fraction and provide the answer as .29?

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### Re: Simple Machines B/Compound Machines C

MP Fan wrote:Coach here... The two distances are rarely whole numbers. So when the students provide their ratios, should they provide fractions or should they resolve the fractions?

As an example, let's say dA is 18.4 cm and dB is is 5.3 cm. Should their answer for the ratio A/B be 5.3/18.4? Or should they go ahead and resolve the fraction and provide the answer as .29?
Follow the rules! I believe the rules say something about following the standard rules of significant figures, so you should resolve the fraction and apply rules of sigfigs.
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### Re: Simple Machines B/Compound Machines C

chinesesushi wrote:
MP Fan wrote:Coach here... The two distances are rarely whole numbers. So when the students provide their ratios, should they provide fractions or should they resolve the fractions?

As an example, let's say dA is 18.4 cm and dB is is 5.3 cm. Should their answer for the ratio A/B be 5.3/18.4? Or should they go ahead and resolve the fraction and provide the answer as .29?
Follow the rules! I believe the rules say something about following the standard rules of significant figures, so you should resolve the fraction and apply rules of sigfigs.
So many of the supervisors are going to ignore the sig figs again that I'm probably just going to ask them about it (since a lot of other teams will likely ignore it too)
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### Re: Simple Machines B/Compound Machines C

The reason I posted this question is that the rules do not say whether you should resolve each fraction. I've reviewed the materials from the SOSI and the Midwest Coaching Academy. No luck.

We have an invitational Saturday. The students plan to resolve the fractions. We'll see what happens.

It's Division C, so the students know to use sigfigs for all events.

chinesesushi wrote:
MP Fan wrote:Coach here... The two distances are rarely whole numbers. So when the students provide their ratios, should they provide fractions or should they resolve the fractions?

As an example, let's say dA is 18.4 cm and dB is is 5.3 cm. Should their answer for the ratio A/B be 5.3/18.4? Or should they go ahead and resolve the fraction and provide the answer as .29?
Follow the rules! I believe the rules say something about following the standard rules of significant figures, so you should resolve the fraction and apply rules of sigfigs.

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### Re: Simple Machines B/Compound Machines C

A team would probably be wiser if they used whole numbers on the light load side.

It still leaves your question as does it get converted to a decimal, or a plain "as is" fraction or a simplified fraction (where possible).
If it is a decimal, does it need to be presented as 1:1.29 to be totally correct?

I will bet that more than one team will present the ratio as A/B when the question might be ask for B/A.

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### Re: Simple Machines B/Compound Machines C

Hello everyone, I recently made a question marathon for Simple/Compound Machines. Feel free to check it out!
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### Re: Simple Machines B/Compound Machines C

MP Fan wrote:The reason I posted this question is that the rules do not say whether you should resolve each fraction. I've reviewed the materials from the SOSI and the Midwest Coaching Academy. No luck.

We have an invitational Saturday. The students plan to resolve the fractions. We'll see what happens.

It's Division C, so the students know to use sigfigs for all events.

So what ended up happening at the invitational?
Nevada state SO occurs on tau/2 day. Support the correct mathematical constant with all tauists.
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Event: Regional/States
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Bungee: 3/3
Compound Machines: x/1
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### Re: Simple Machines B time to measure ratios of 3 weights

Hi,
Wanted to find out what times other schools are getting for measuring the ratios for the 3 weights. We are currently able to complete measuring the ratios for the 3 weights in 2 minutes and 30 seconds. Is this good enough to do well at regionals and state?

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