(model
 (true := true) 
 (false := false) 
 (a := 5/3) 
 ((* 3 a) := 5) 
 (5 := 5) 
 ((= (* 3 a) 5) := true) 
 ((<= (* 3 a) 5) := true) 
 ((>= (* 3 a) 5) := true))