proposition: Lemma prob_mulr {R : realType} (p q : {prob R}) : (0 <= Prob.p p * Prob.p q <= 1)%R.
proof: Proof. apply/andP; split. by rewrite mulr_ge0. by rewrite mulr_ile1. Qed.
imports: mathcomp(all_ssreflect ssralg ssrnum) mathcomp(reals normedtype) mathcomp(mathcomp_extra boolp) mathcomp(lra ring Rstruct)