The answer at the back of the book is A. My answe I got 172 NM and Time was 63 minutes.

ETP= 298×223÷386=172 NM

Time- 172÷GS on(163)= 63 minutes.

To find time which GS I'm going to use?

The anser on the book says (A) is the correct answer..which means ETP=298×223(GS Home)÷386=172 NM

what about the time? I'll have to use the GS home also?

172÷223=46 Minutes?

Can anyone clear this up for me? need help

You have made a very simple error in reading the question. The question asks for the "distance and time from the ETP back to Ceduna". This, of course, will require consideration of the return G/S. Had the question asked for the numbers relating to the outbound segment to the CP, your answer would have been just fine.

Your commentary shows, quite clearly, that you have no difficulty with sorting out the calculations - just needed a little more precision in reading and interpreting the question's requirements.

The only other consideration, which is not relevant to CPL but would be for any folk going on to bigger aircraft, is that one could refine the answer by considering the weight changes as fuel burns off. These affect the TAS and, hence G/S. However, for small aircraft the differences generally are fairly trivial. For this example, the differences are less than a mile and a minute so it is entirely appropriate to work the question without consideration of weight changes.

In an environment where the exam is run by computer, the examiner has no means of considering the work you do in figuring the question. The computer only sees a correct/incorrect answer.

In the olden days, you probably would get a part mark for the question for a simple interpretation error but there is no provision for this with computer exams. It is essential, with all the CASA exams, that the candidate reads the question with a view to precise comprehension. If one makes a mistake in working out what the examiner is after, the result is pretty well a foregone conclusion. Do this for enough questions and it is a case of coming back for another exam attempt next time when, in fact, you might be quite competent at all the calculations - not a useful strategy for securing a pass first time.

I do quite a bit of training work with foreign pilot students (a plug for Bob - that organisation makes considerable use of the BT texts) and, for folk without English as a first language, the CASA exams can be extremely difficult when it comes to wading through the idiomatic twists and turns of linguistic interpretation. Those folk manage to do just fine (albeit with a fair bit of work on their part) so the local domestic folk should be able to do the same ?