what is the star system that has an age less than 4.6e+09?
Entity
m.02wbnmn
HD 98800
class literal
astronomy.star_system 4.6e+09^^http://www.w3.org/2001/XMLSchema#float
astronomy.star_system type.float
Star System 4.6e+09
none <
astronomy.star_system.system_age
System Age
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> PREFIX : <http://rdf.freebase.com/ns/> 
SELECT (?x0 AS ?value) WHERE {
SELECT DISTINCT ?x0  WHERE { 
?x0 :type.object.type :astronomy.star_system . 
FILTER (?x1 < "4.6e+09"^^<http://www.w3.org/2001/XMLSchema#float>)
?x0 :astronomy.star_system.system_age ?x1 . 
FILTER ( ?x0 != ?x1  )
}
}
(AND astronomy.star_system (lt astronomy.star_system.system_age 4.6e+09^^http://www.w3.org/2001/XMLSchema#float))