PREFIX  dc:  <http://purl.org/dc/elements/1.1/>
PREFIX  ns:  <http://example.org/ns#> 
SELECT  ?title ?price
WHERE   { ?x ns:price ?price .
          FILTER (?price = 30 * 10 * (4 + 5 - 3) - 4 / 2) . #4 + 5 + 6 - 3
          ?x dc:title ?title . }