How would you find the fraction of a circle that an arc covers?

A. Divide the circumference by 360.
B. Divide the measure of the arc by 180.
C. Divide the diameter by 360
D. Divide the measure of the arc by 360.

Question

How would you find the fraction of a circle that an arc covers?

 		A.	Divide the circumference by 360.
 		B.	Divide the measure of the arc by 180.
 		C.	Divide the diameter by 360
 		D.	Divide the measure of the arc by 360.

raffle_snaffle · Answer

well we know it's not?

ffasinger · Answer

I know it is not B

misssmartiez · Answer

http://www.answers.com/Q/How_would_your_find_the_fraction_of_a_circle_that_an_arc_covers

misssmartiez · Answer

Take a look at it.

ffasinger · Answer

I just did.

misssmartiez · Answer

Do you know now?

misssmartiez · Answer

Or more clarification?

ffasinger · Answer

A I think

misssmartiez · Answer

What do you think mathmale? I'd say A also, http://www.nelson.com/school/elementary/mathK8/quebec/0176237879/documents/NM8SB_5A.pdf Since I don't see an answer saying anything about the 'central angle'.

mathmale · Answer

Please, could we focus on understanding instead of just answers?  answers.com will not be available to you during exams.

If an arc length of less than one whole circumference is given to you, write the RATIO

$$\frac{ given~arc~length }{ 2\pi r }=\frac{ r \theta }{ 2 \pi r }.$$

ffasinger · Answer

hmmm

mathmale · Answer

Notice that you can reduce the last result by cancelling out the ' r '   
This fraction is the answer to your question, so long as you express your angle (theta) in radians (not in degrees).

ffasinger · Answer

ok so it is A

rockycatsrule · Answer

that seems correct to me

mathmale · Answer

Can you convince me that "A" is the same thing as I've suggested (using that formula)?

misssmartiez · Answer

I'd say so. 

The others don't touch on what we went over. Basically the only thing that makes sense. However. do you know WHY it is A?

mathmale · Answer

Suppose that I tell you that the length of the arc is 5.  What fraction of the whole circular area is represented by that arc length and the corresponding, pizza-slice-shaped area?

mathmale · Answer

Hint:  It's more than half the circle but less than the full circle.

mathmale · Answer

Write your answer as a proper fraction.

rockycatsrule · Answer

i dont want to give a direct answer

rockycatsrule · Answer

cuz that would be agenst contract

mathmale · Answer

Any explanation you'd like to provide, as an alternative to others' answer choices, would be welcome.  You don't need to give the answer, but you could certainly explain how you or FFASinger could go about finding it.

rockycatsrule · Answer

well i could be wrong but everyone makes misstakes

rockycatsrule · Answer

but u said it would be half so basiced on that formula i got 180

phi · Answer

one way to figure it out.  look at a simple case
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