Answer:
Area ~= 52.4 m^2
OR (see image why)
Area ~= 52.3 m^2
Explanation:
Use A = pi•r^2 to find the area of the whole circle. For a sector, times that by degrees/360.
Your problem has a 60° sector. 60/360 is 1/6.
Use either, 60/360 or 1/6 times 100pi.
If you use the pi button on the calculator the answer is .1 different than if you use 3.14 for pi in your calculation. The pi button answer is more accurate. See image.