Qs34 Mercury training

Hello Could you please clarify me on the qs 34 named Mercury training in bpp kit ..we are averaging the asset beta for Mercury ..why we are averaging ..also the figures it 0.67 * 1.3865 ,+ 0.33*0.75 .I don't understand the figures 0.67 and 0.33 where do they come from ..the beta asset 1.3865 is for Jupiter and 0.75 is for financial services asset beta And while writing u this query I realise that the question says that financial services account for one third of the total revenue of Mercury so is it the figures 1/3 ...0.33 is assigned to financial services and the rest to training business Am I right ? I would like to understand why we take the average .are we always going average asset beta for company in every question. Thank in advance .