Random Variables, Slide 5:  change "\cup_i" to "\sum_i" after "="
Random Variables, Slide 8:  change "discrete or" to "discrete nor"
Discrete Random Variables, Slide 6:  change "X >= x" to "X <= x"
Mathematical Expectation, Slide 35:  change "p = 1/4" to "p = 1/2"
Functions of Random Variables. Slide 30:  change "f_y(y)" to "f_Y(y)"