Metamath Proof Explorer


Theorem probvalrnd

Description: The value of a probability is a real number. (Contributed by Thierry Arnoux, 2-Feb-2017)

Ref Expression
Hypotheses probmeasd.1
|- ( ph -> P e. Prob )
probvalrnd.1
|- ( ph -> A e. dom P )
Assertion probvalrnd
|- ( ph -> ( P ` A ) e. RR )

Proof

Step Hyp Ref Expression
1 probmeasd.1
 |-  ( ph -> P e. Prob )
2 probvalrnd.1
 |-  ( ph -> A e. dom P )
3 unitssre
 |-  ( 0 [,] 1 ) C_ RR
4 prob01
 |-  ( ( P e. Prob /\ A e. dom P ) -> ( P ` A ) e. ( 0 [,] 1 ) )
5 1 2 4 syl2anc
 |-  ( ph -> ( P ` A ) e. ( 0 [,] 1 ) )
6 3 5 sselid
 |-  ( ph -> ( P ` A ) e. RR )