Cost: the amount of resources(in monetary terms) sacrificed to achieve a particular object Two types of cost for decisions : Historic cost - a cost already incurred Opportunity cost -the value of an opportunity forgone(sacrificed) Historic costs are not directly involved in the decisions we make • Does the cost relate to the objective/improve business, relate to the future, and vary with the decision, if not then it's irrelevant. If it does matter with all these 3 points then it's a relevant cost Minimum cost 9000 +1000 because of 50 times 20 and add this to 2,500 Which is 12,500 It’s a relevant cost as the cost vary with the decision, wouldn't need to be replaced Historic costs irrelevant, re sale value 800*12 = 9,600 As it's an opportunity cost, forgone and the alpha business is no longer used £300 for each Irrelevant cost since it doesn't vary Minimum price Opportunity cost of the lord £9000 Cost of new engine £2500 Add together is = £11,500 Alternative route is better Better to not spend 2,500 Behaviour of costs Fixed cost remain constant/fixed when changes occur to the volume of activity Variable cost vary according to the volume of activity Relevant costs are one of the areas of decision making, and in that it's for one off type decision, e.g. contract type decisions and so relevant cost decisions become very important, and so those which aren't run of the mill, we look at the other two distinct type of costs, in relation to the volume of activity, and distinguish those whether they are relevant/fixed and variable. We tend to think of the business as a whole and we want to see the survival of the cost. The fixed cost still needs to cover the whole business and you as a whole, even though it doesn't vary. • Production and output must provide a profit at the end of the day, that must include the fixed costs -Multi product businesses Calculating the Break Even Point Contribution per unit Revenue - variable cost- fixed cost Break even point is where the profit is 0 Is 0 profit The Q*/ or B* is the break even point Q has to do with quantity So Contribution per unit can summarise the sales venue and the variable cost Just putting the q on the other side to get the quantity