For the time suck comment I was referring to the second question
Noted - my error.
by the time the candidate realises it's a waste of time, better questions could have been answered.
The question took me a similar time to the first to sort out - about 30 seconds to run up a quick sketch (for those folk who don't draw a sketch, you are just making things difficult for yourselves, quite unnecessarily). It was obvious that the solution was q.e.d. if the datum were to be moved. The sums took about 10-15 seconds to do to the point where it was evident that the question was flawed. The question, as they say, is money for jam and dead easy to do.
I would suggest that the question is anything but a waste of time. It has some unusual characteristics which have a very useful learning outcome. So far as the error in the question is concerned, that would have been simple finger trouble on the part of whoever wrote the question, allied with either no/inadequate checking prior to publishing the question - I think most of us have been guilty of such things over the years.
The various stages required should be one mark questions.
If you prefer. However, I would put the question as being worth, maybe 2 marks in a typical exam so not really worth the effort in making the change ?
It looks like a simple moving mass question,
Why ever would you think that ? If you did, then you would be off on a tangent with no solution in sight.
in that the C of G has to be moved 7%,
Indeed. However, one can ballast (in this case by adding fuel) to achieve the goal.
but it isn't.
That ought to have been evident from the initial assessment of the question.
Perhaps you might post your solution and we can offer constructive critique ? That way there is a positive learning outcome for those who might be interested in this thread ?
Unfortunately, far too many pilots try to learn too little about weight control and then find themselves thrashing about in a bog when hunting for problem solutions. With a bit of background understanding, weight and balance stuff is easy peasy and absolute money for jam in the examinations.