Casio EX-FC100 has a 9.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized CMOS sensor . On the other hand, Fujifilm S8300 has a 16.0MP 1/2.3-inch (6.17 x 4.55 mm ) sized BSI-CMOS sensor .
Fujifilm S8300's sensor provides 7MP more than Casio EX-FC100's sensor, which gives a significant advantage in real life. You can print your images larger or crop more freely.
On the other hand, please keep in mind that Max sensor resolution is not the only determinant of resolving power. Factors such as the optical elements, low pass filter, pixel size and sensor technology also affects the final resolution of the captured image.
Below you can see the EX-FC100 and S8300 sensor size comparison.
Casio EX-FC100 and Fujifilm S8300 have sensor sizes so they will provide same level of control over the depth of field when used with same focal length and aperture.