In the above schedule, we can see that when a consumer consumes additional units of orange then the total utility inclines at first at an increasing rate, remains constant for some period and then starts declining. With additional consumption of oranges, marginal utility declines, reach zero and become even negative. It can also be expressed by the following diagram:


From the above schedule and diagram, we can summarize the relationship between Total Utility and Marginal Utility as follows :

1. Total utility is the sum of total marginal utility. Marginal utility is the change in total utility.
2. Total utility generally remains positive while marginal utility may be positive, zero or even negative.
3. When marginal utility is positive, total utility rises.
4. When marginal utility is zero, total utility is maximum.
5. When marginal utility is negative, total utility falls.