 module 13 and difference curves. We may have utility under cardinal approach and cardinal approach. Cardinal approach is a way where we can measure utility. Under cardinal approach we assume utility that someone is getting from a particular commodity is independent from the quantities of other commodities. But in reality utility that someone is getting from a particular commodity is also depends upon the level of quantities of other commodities. For example usage of loaf without butter will give you a certain level of satisfaction. But when we use loaf with butter then there is some change in level of satisfaction that someone is getting from the consumption of loaf. Similarly if we make the utility that someone is getting from a slice without using jam it will be some will be different than if someone is using the same slice along with jam. So utility that someone is getting from the consumption of one commodity it depends upon the available depends upon the quantities of other commodities too. And similarly under cardinal approach we assume we can add utility that we are getting from different commodities. And the utility that we are getting from different commodities are independent from the quantities of other commodities. And these are this is an unreasonable approach to measure the utility. While under cardinal approach we assume consumer is getting satisfaction from a consumption bundle. And that consumption bundle usually includes our large number of goods and services. And the utility that someone is getting from a particular commodity it depends upon the quantity of other commodities too. Under ordinal approach we are also in a position to rank different to rank the level of satisfaction against different consumption bundles. And we are not measuring the utility numerically we are only making a comparison where we are assigning ranks we are assigning orders to different levels of two different consumption bundles. For example again if we are considering the example of apples and oranges your consumer is using apple and oranges to get satisfaction against different combinations of apples and oranges he will get a certain level of satisfaction. But against those different combination of apples and oranges we are in a position only to rank orders to different consumption bundles. We are not in a position to say because someone is getting 25 euros of utility against this particular combination of apples and oranges and 50 units euros of utility against another combination of apples and oranges. We can only say consumer is getting more satisfaction from a particular combination of apples and oranges as compared to another combination of apples and oranges. And to elaborate the order of the preferences of the consumer we usually use the concept of iso utility. Iso means same and utility means satisfaction. So, iso utility is iso utility curve or indifference curve is a curve that shows different combination of commodities against which a consumer is getting same satisfaction. To keep things simple we assume consumer is getting satisfaction by using only two commodities. If we assume those two commodities are apples and oranges in real life a consumer is in fact using a large number of commodities. But to keep things easy to keep things understandable we start by making an assumption consumer is getting satisfaction by using apples and oranges. In this diagram which shows different combinations of apple and oranges that provide same level of satisfaction to a particular consumer. So, by using one apple and ten oranges consumer is getting a certain level of satisfaction and that same level of satisfaction can be achieved by that particular consumer by using two apples and five oranges. Same level of satisfaction can also be obtained by using three apples and two oranges. So, again different combination of two commodities that provides same level of satisfaction every represent those things graphically we use a curve to which we called as iso utility curve or indifference curve. Whenever we make study about the indifference curve again we start may we start we formulate certain assumptions. First of all under the theory of the preferences we assume consumer can assign rank to all the consumption bundles that are available for consumption. Consumer can make an ordering of all the consumption bundles that are available for his consumption. Secondly there is no point of saturation, there is no point of saturation, there is no point of saturation more is always preferred over less. So, an indifference curve shows the same level of satisfaction along all the points that lie on a particular indifference curve and a higher indifference curve indicate a higher level of satisfaction at and each indifference curve is associated with a different level of satisfaction. The indifference curve that we considered here is convex to the origin. It might be possible our indifference curve is a negatively sloped straight line. It might be possible our indifference curve are right angled curve depending upon the nature of the commodities. If indifference curves are right angled curve then the two commodities that are under consideration for consumption are perfect complement. And if we consider two commodities are perfect substitutes then our indifference curve is a negatively sloped straight line. But when we assume consumer preferences are well behaved preferences then our indifference curve is convex to the origin and more is always preferred over less. As I have already mentioned higher the indifference curve higher the level of satisfaction in this diagram by taking apples on horizontal axis and oranges on vertical axis. We are showing here theory indifference curves IC1, IC2 and IC3. Among these three indifference curves IC3 indicate a higher level of satisfaction as compared to IC2. IC2 indicate a higher level of satisfaction as compared to IC1. But along each indifference curve level of satisfaction of the consumer is constant. There is no change in level of satisfaction along a particular indifference curve. Any combination that lie on any difference curve provides same level of satisfaction but IC3 indicate a higher level of satisfaction as compared to IC2. So under ordinal approach by using indifference curve we can assign ranks to all the consumption bundles that are available for consumption to a particular consumer. Higher the indifference curve higher the level of satisfaction and that is all in this module. Thank you.