A wall clock is 12 inches in diameter. The clock has twelve equally spaced numbers. What is the distance around the edge of the clock from 8 to 12?

π

4π

3π

2π

Question

A wall clock is 12 inches in diameter. The clock has twelve equally spaced numbers. What is the distance around the edge of the clock from 8 to 12? 

 π 

 4π 

 3π 

 2π

anonymous · Answer

@Hero

ivettef365 · Answer

C = d. pir     d=12

C = 12pi, so divide 12/12 x 4

anonymous · Answer

so 4

ivettef365 · Answer

correct

anonymous · Answer

ok thanks

hero · Answer

This is a proportion problem dealing with distance vs degree measure. So we'll need to use the following formula:

$$\frac{\text{distance from 8 - 12}}{\text{circumference of the circle}} = \frac{\text{degree measure from 8 - 12}}{360}$$

hero · Answer

The distance from 8 - 12 is what we need to find so we let that be x. The degree measure from 8 - 12 represents 1/4 of 360 or 45 degrees so. The circumference of the circle is 2pi*r or d*pi = 12pi

$$\frac{x}{12\pi} = \frac{45}{360}$$

Solve for x.

hero · Answer

@iFlexzatious

anonymous · Answer

thanks its 4

hero · Answer

Negative. It's not 4

hero · Answer

Solve the proportion above for x.

anonymous · Answer

I don't get I get 4pi

hero · Answer

It's not $4 \pi$. Sorry to disapoint you.

hero · Answer

@ivettef365, why did you tell him $4\pi$ was correct when it isn't?

anonymous · Answer

so then can u break it down for me more plz

hero · Answer

@iFlexzatious, do you know how to solve the proportion I posted above?

anonymous · Answer

no I don't understand that

hero · Answer

You don't understand how to solve this for x:

$$\frac{x}{12\pi}= \frac{45}{360}$$

anonymous · Answer

cross mutiply

hero · Answer

45/360 reduces to 1/4 so:

$$\frac{x}{12\pi} = \frac{1}{4}$$

hero · Answer

There, I just made it even easier for you.

anonymous · Answer

4x=12pi

anonymous · Answer

x=3

hero · Answer

$$x = 3\pi$$

anonymous · Answer

3pi

anonymous · Answer

thanks a lot can u come check this one out plz

ivettef365 · Answer

still don't understand because from 8 - 12 is 1/3 of the Circumference
C = 12 pi and 1/3 = 4

anonymous · Answer

45/360 reduces to 1/4 so:

hero · Answer

Actually, @ivettef365 is right.

hero · Answer

the proportion is

$$\frac{x}{12\pi} = \frac{120}{360}$$

anonymous · Answer

cross multiply 
4*x=4x
1*12=12pi
therefore 
4x=12pi
4/12pi=3pi
@ivettef365

hero · Answer

$$\frac{x}{12\pi} = \frac{1}{3}$$

anonymous · Answer

3x=12pi
x=4pi

hero · Answer

Which becomes $3x = 12\pi$. 

$x = 4\pi$

anonymous · Answer

whats the right answer here