I've changed 3 hoses on my 2006 X 3.0, not 100% sure that Rack lost the liquid, but to fill back up was less then a quart, A lot less. As was recommended here in the forum, I filled up, let the engine run, sucked all all the fluid out, refilled - about 2-3 time before that quart ran out.
So if you have/buy a quart - it should be safe to say that it is enough to refill your system, whatever you plan on doing with it.

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2009 Range Rover Sport SC HST Limited Edition
2014 Infiniti Q50 AWD