The area of a circle is 225 pie square inches. find the area of the sector whose central angle is 45°.

Consider this option:
The central angle for whole circle is 360°, it means that angle 45° has 45/360=1/8 part of the circle.
If the area of the circle is 225π, then the area of the sector 45° is 225π/8≈28.125π (in.²)

28.125π in².

Just turn the whole gym into pie