Question: Give me an estimate of the number of manufacturers whose products are managed by MTR?
SPARQL query: SELECT DISTINCT COUNT(?uri) WHERE { ?x <http://dbpedia.org/ontology/operator> <http://dbpedia.org/resource/MTR> . ?x <http://dbpedia.org/ontology/manufacturer> ?uri  . }
Answer: There are [12] manufacturers whose products are operated by MTR.