Magnification of compound microscope is not connected with numerical aperature. The magnifying power is represented by the symbol 'X\, The total magnification of a microscope is obtained by multiplying the objective magnification and ocular lens magnification e.g., if the magnifying power of an ocular lens is 1 OX and of the objective is 40X, then the total magnifying power of a microscope is 10 x 40 = 40X.