If I can follow your method, step by step, showing each calculation, there's a good chance you'll score on the question. eg. If a decimal point is put in the wrong place, you will be penalised for that. Of course, that will throw the whole calculation out, but, as you have been penalised for the initial mistake, it won't lose any more for that mistake. The rest of the calculation is followed and, if there are no other mistakes, there will be no other lost marks. The correct answer is worth only 10% of the value of the question. If you are a wizard with a calculator and put only the correct answer for the question, you will fail. Yes, I've done it before. The Rules state quite clearly to show your working.
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