Answer:
To name substituted alkenes, the unsaturation is numbered lowest, followed by any substitutions; so as it is written, these rules are not followed, for clearly hexene indicates an unsaturation. It COULD be (2,4) dimethyl-(1)-hexene, but then again, as “Dimethyl 2,4 hexene” it could be a lot of things. Two unsaturations would be denoted as “hexadiene“, but it is not.
Explanation: The name appears incomplete.