SOLUTION: My grandson is working this problem((A=80cm2 then there is a circle with a 45 degree area blacked out)). He is supposed to use a proportion to find the area of each shaded sector.

Algebra ->  Proportions  -> Lessons -> SOLUTION: My grandson is working this problem((A=80cm2 then there is a circle with a 45 degree area blacked out)). He is supposed to use a proportion to find the area of each shaded sector.      Log On

45 degrees is to 360 degrees as the area of the sector is to the area of the whole circle:

45°:360° = x:80cm²



360x = (80)(45)
360x = 3600
   x = 
   x = 10

The area of the sector is 10 cm²

Edwin