Can you repost this with the picture
A=abby's shirts
b=bik's shirts
c=cari's shirts
d=dawn's shirts
e=ellen's shirts
a> everybody
b=2.5c
d=(1/3)c
a+b+c+d=120
e=2d+1
e=13
oook
e=13=2d+1
13=2d+1
12=2d
d=6
d=(1/3)c
6=(1/3)c
18=c
b=2.5c
b=2.5(18)
b=45
a+b+c+d=120
a+45+18+6=120
a+69=120
a=51
If you have 60% out of 40 students that is 24 students
120º is 1/3 of a complete revolution of 360º. So the area of this sector should be 1/3 the area of the complete circle.
A circle with radius 9 has area 9^2 π = 81π.
So the sector has area 81π/3.
Put another way: The area <em>A</em> of a circular sector and its central angle <em>θ</em> (in degrees) occur in the same ratio as the area of the entire circle with radius <em>r</em> according to
<em>A</em> / <em>θ </em>º = (π <em>r </em>^2) / 360º
==> <em>A</em> = π/360 <em>θ r</em> ^2
In this case, <em>r</em> = 9 and <em>θ</em> = 120º, so
<em>A</em> = π/360 * 120 * 81 = 81π/3
It cannot be simplified...
