Olympus E-PL5 has a 16.0MP Four Thirds (17.3 x 13 mm ) sized CMOS sensor . On the other hand, Hasselblad X2D has a 101.8MP Medium format (44 x 33 mm ) sized CMOS sensor .
Hasselblad X2D's sensor provides 85.8MP more than Olympus E-PL5'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 E-PL5 and X2D 100c sensor size comparison.
As seen above, Hasselblad X2D has a 6.5x Larger sensor area than Olympus E-PL5. Larger sensors give photographer more control on the depth of field and blurry background compared to smaller sensor when shot in same focal length and aperture.