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 F900EXR has a
16.0MP 1/2-inch (6.4 x 4.8 mm ) sized EXRCMOS sensor and features EXR II processor.
Fujifilm F900EXR'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 F900EXR sensor size comparison.
Casio EX-FC100 and Fujifilm F900EXR have almost the same sensor size, so neither of them has any significant advantage over the other in terms of providing control over depth of field when used with the same focal length and aperture.