What is the radius of a circle with a circumference of 23.55 meters? Use 3.14 for pi and show your work.

Question

What is the radius of a circle with a circumference of 23.55  meters? Use 3.14 for pi and show your work.

anonymous · Answer

please help me

shane_b · Answer

$$C=\pi d$$You know C and pi...and $$r=\frac{d}{2}$$so...what do you think you need to do?

shane_b · Answer

Or you could just blurt out the answer...which is *almost* correct.

anonymous · Answer

lol

shane_b · Answer

@yoyogators: Do you understand what to do at least?  His answer only has a simple math error but the process is right.

anonymous · Answer

i dont trust him so can you give me step by step on how to get the correct answer?

shane_b · Answer

Ok...$$C=\pi d=\pi (2r)$$With me so far?

anonymous · Answer

Blurting out the answer with work :D

anonymous · Answer

hold on

anonymous · Answer

maybe you`ll need this: 
C = 2πr
substitute the values
23.55=2(3.14)r
23.55=6.28(r)
r=3.75m

anonymous · Answer

What is the radius of a circle with a circumference of 23.55  meters? Use 3.14 for pi and show your work.

anonymous · Answer

ok so that is the answer

shane_b · Answer

I think it's better to walk them through it and lead them to the answer...seeing the full answer right away is not always helpful.

anonymous · Answer

ok so they want to know what the radius is

shane_b · Answer

Right...and you know the circumference and pi.  All this problem is is solving the formula for r.

shane_b · Answer

$$C=\pi(2r)$$So solving for r what do you get?

anonymous · Answer

so the r is half way in and if the circumference is 23.55

shane_b · Answer

yes...good so far.

shane_b · Answer

Forget the numbers for a moment and just solve the formula for r.  Plugging in the values later is trivial.

anonymous · Answer

so you would divid 23.55 by 3.14 then divid by 2

shane_b · Answer

Correct.  You end up with $$\frac{C}{2\pi}=r$$

shane_b · Answer

Now just plug in the values you were given.

anonymous · Answer

so if that is correct the raduis is 3.75

shane_b · Answer

Yes.

anonymous · Answer

so hold on is this correct

anonymous · Answer

You have to subtract the 1 first

4/5 and 5/6
Make the denominators equal 
24/30, 25/30
Jake has the smaller fraction which means his time is lower.. Or divide top number by bottom and the smaller decimal wins.

Divide 23.55 by pi, then divide by 2.

anonymous · Answer

opps pellet that is the wrong thing sorry

anonymous · Answer

S     H     I     T      not pellet

shane_b · Answer

Both of your assertions in the other question are correct.  If the denominators are the same, the smaller one is the smaller amount.  Or you can simply divide each fraction and the smaller decimal is the smaller value.

anonymous · Answer

ok so you would say 



to find what the radius you have to get 23.55 divid that by 3.14 then divid that by 2 and the answer will be 3.75

anonymous · Answer

ok so is what i wrote correct to the question

shane_b · Answer

Yes...or you could simplify more by saying:
"Take the circumference and divide it by 2 times pi to get the radius"

anonymous · Answer

ok thanks man you are a life saver i will give you a metal!!!!!!!!

shane_b · Answer

No problem..good luck

anonymous · Answer

o i have one more sorry

anonymous · Answer

Which of the following is not a true statement?

 Pi is the ratio of a circle's circumference to its diameter.

 The center of a circle is the distance from one point on a circle to the opposite side.

 The radius of a circle has one endpoint at the center and the other endpoint on the circle.

 The circumference of a circle is twice the product of  and its radius.

shane_b · Answer

Take a look at the formula: $$C=\pi2r$$Now solve it for pi:$$\pi=\frac{C}{2r}$$
So which answer does that look like?

shane_b · Answer

Still here?

anonymous · Answer

ya sorry my mom called me

anonymous · Answer

ok let me look

anonymous · Answer

The center of a circle is the distance from one point on a circle to the opposite side.

shane_b · Answer

Ok, let's start with that.  The question is stating that the center of a circle is the length of the line in the drawing:|dw:1339957616749:dw| Is that true?

anonymous · Answer

yes

shane_b · Answer

No :)  The length from one side of a circle to the opposite side is the diameter..so that statement is false.

shane_b · Answer

All of the other statements are true if you think about them.

anonymous · Answer

ok the wrong statement is The center of a circle is the distance from one point on a circle to the opposite side.

shane_b · Answer

Right

anonymous · Answer

ok thanks i will remember that now!

shane_b · Answer

k, good luck

anonymous · Answer

|dw:1408144701235:dw|