Interpretation

You need to practise the past exam questions and use the model answer to help you identify what you need to do to pass. There are also some revision videos that cover the approach to this type of question. the key initially is to crack on with calculating the required ratios (the easy part) and then use the information in the question to help you understand the reasons behind the movement in the number/ratio. The information in the question is key to doing well in this type of question as it is effectively telling you the answer! Thanks