Rotational symmetry is attained on a figure if it is possible to achieve the same image of the figure after rotating it. For example , rotating a circular plate marked with numbers 1 to 6 through a 360° rotation, the number marked 1 with attain a position similar like that before rotation.
In general, the probability is the ratio of the number of favorable outcomes to the total outcomes in that sample space. It is expressed as, Probability of an event P(E) = (Number of favorable outcomes) ÷ (Sample space).