P/E Ratio

Hi John, If, for example a question gave you the information to calculate the P/E ratio of that particular company but also gave you what a similar company's P/E ratio was and then asked you to calculate the share price using the P/E ratio method, would you lose marks if you didnt use the similar company's P/E ratio and instead used the actual company's P/E ratio seeing as they gave you enough information to calculate it? Thanks Graham