I've recently purchased the Performance and Planning ground effect exams and have stumbled across a few questions I do not understand. Attached below are the questions, ive tried multiple time and feel like im missing something
Q7
-I found take off safety speed for max-weight, then with that found feet covered horizontally in a minute, then used the climb gradient of 6% to find required min rate of climb required to be 504, where the answer is 516

Q8
-first I found that the centre of gravity was outside its limitations to the rear so I put 40kg of ballast in the nose to then make it in balance, requiring no ballast fuel, though the answers indicate that there needs to be ballast fuel

Q17
-I simply multiplied 62 by 1.15 to aquire the variable reserve then added on the fixed and taxi converted it to kg and added it to the zfw, although this answer was not correct

I think, perhaps, both you and other students will get better value out of this question if you include your solutions. That way, we can work through them to whatever might be correct and you get to see the working logic along the way ?

It does not, necessarily, follow that your solution is incorrect and the suggested solution is correct .. sometimes there be errors in the text.

In any case, if we just nominate the answer, no learning value occurs.

I suggest that you contact Ground Effect for the solutions to those questions. It is our policy to provide worked solutions only for our own questions for our own students.

I'm sure those instructors will be happy to assist.

All the best with your study.