MULTIPLE CHOICE. help will become fan.

Question

anonymous · Answer

attachment

moonlitfate · Answer

@Foreverisabell -- do you know  how to start the problem? :)

anonymous · Answer

boo

anonymous · Answer

*no

moonlitfate · Answer

All right; well the information that's given to you from the problem is that:

The diameter of the = 22
The central angle = 20 degrees. 
The formula for the area of a sector is:$$Area = \frac{ \theta }{ 2 }r^2 (radians)$$ or $$Area = \frac{ \theta }{ 360 }\pi r^2 (degrees)$$; where r is the radius of the sector and theta is going to be the central angle; are you with me so far?

anonymous · Answer

yes so would you do 22/360? times pi times 11^2?

moonlitfate · Answer

Yes. :)

anonymous · Answer

here 	heta\ is 160 i guess...

anonymous · Answer

i get 23.21?

anonymous · Answer

thats not in my answers though?

moonlitfate · Answer

Oh, wow!  I'm sorry.  I did the area of the wrong sector; sorry.

anonymous · Answer

thts because u r using theta=22... it is theta=(180-20)=160... tht gives the answer as 168.9 (approx)

anonymous · Answer

Thank you @xavier123 How would you do this one then?

moonlitfate · Answer

@xavier123 -- is correct. :p  The central angle of the bigger sector is 160 degrees; I was misread the problem and did the area of the smaller sector.

anonymous · Answer

for the whole circle (ie theta = 360) my length of arc is nothing but (2*pi*radius) so for theta = 125 it should be (2*pi*radius)/360 * 125... surely u can calculate now... these questions are basically based on "direct proportions".