Sentence:  “I can't tell you what we're going back to consider,” said Darrell Jordan, a special prosecutor assigned to the case, who cited Texas law regarding grand jury secrecy. “But you can <WSD>do the math</WSD> and figure out what it is.” 
Meaning of the word marked with <WSD> tags:  To make a thoughtful effort to determine the motive for someone's behavior; to develop one's own understanding of the explanation for or precise nature of a situation.