I feel this comment betrays a misunderstanding of what language even is. Saying it like “two forty-five” or whatever is a figure of speech as much as “quarter to three” is.
No, I meant it. “Two forty-five” is a figure of speech. If you were giving the time in exact terms you’d say something like “it’s been two hours and forty-five minutes since midday/midnight”. You’re just stuck in this idea that your way of expressing it is the right one.