Translation:You start at six thirty five.
"You start at 6:35" should be accepted rather than "You start at 6:30 five"
obviously six thirty five is most suitable
The translation given is incorrect in English. It ought to read: "You start at six thirty-five." with a hyphen between thirty and five, as numerals between twenty-one and ninety-nine are hyphenated when spelled out.
Furthermore, the answer "You start at 6:35." ought to be accepted as correct.