step 1
Find the area of the complete circle
A=pi(r^2)
we have
r=10 in
A=pi(10^2)
A=100pi in2
step 2
Remember that the area of complete circle subtends a central angle of 360 degrees
so
Applying proportion, find out the area of the ector by a central angle of 60 degrees
so
100pi/360=x/60
solve for x
x=100pi(60)/360
x=(100/6)pi in2
simplify
area is (50/3)pi in2
