Work out 2 ÷ 500 (6)
I believe the answer is:
deduce
'work' is the definition.
The definition and answer can be both related to thinking as well as being verbs in their base form.
Maybe there's a link between them I don't understand?
'out 2 500' is the wordplay.
'out' indicates putting letters inside.
'2' becomes 'deuce' (synonyms).
'500' becomes 'D' (Roman numeral for 500).
'deuce' placed around 'd' is 'DEDUCE'.
(Other definitions for deduce that I've seen before include "Arrive at conclusion through reasoning, as Sherlock Holmes did" , "Arrive at conclusion through logic" , "Reason out (something)" , "Reason through logic" , "Arrive at reasoned conclusion from facts" .)