Translation:The Prime Minister's office is open from nine to four thirty.
No, the form וָחֵ֫צִי is used for half past (the hour). Although the original form of the noun half is חֲצִי, its biblical pausal form replaced it as the abolute form and delegated חֲצִי to the construct. By the way, וָ is the form of the conjunction and used directly before a stressed syllable when conjoining paired words.
Well, downvotes should not pull at your heartstrings. I see them all the time without obvious reasons. I suppose only when massive downvoting happens and angry threads follow, one may reconsider ones words. It is healthier to follow the maxim: "if you are holding out for universal popularity, I'm afraid you will be in this cabin for a very long time".