Question Number 134296 by EDWIN88 last updated on 02/Mar/21
Answered by bramlexs22 last updated on 02/Mar/21
$$\mathrm{total}\:\mathrm{three}\:\mathrm{digit}\:\mathrm{numbers}\:=\:\mathrm{4}×\mathrm{5}^{\mathrm{2}} =\mathrm{100} \\ $$$$\mathrm{the}\:\mathrm{number}\:\mathrm{has}\:\mathrm{identical}\:\mathrm{digit}? \\ $$$$\left[\:\mathrm{111},\:\mathrm{333},\:\mathrm{555},\:\mathrm{999}\:\right]\:=\:\mathrm{4}\:\mathrm{numbers} \\ $$$$\mathrm{the}\:\mathrm{p}\left(\mathrm{A}\right)=\:\frac{\mathrm{4}}{\mathrm{100}}\:=\:\frac{\mathrm{1}}{\mathrm{25}} \\ $$