IN economics what's the formula in solving for the total utility?

Answer 1

Usually there is no formula. Utility is an abstract concept that economist assume describes what people want and that has some general properties, such as more is better. Sometimes a function is given in classes to make the abstraction more concrete to help student's understanding. In this case utility is obtained by substituting the products that a person buys into the given utility function.

Answer 2

First let some one clarify: Is utility a form of wealth? Let him also name the science that deals with nature, properties, composition, laws and classification of wealth.
Coming to utility, think for a while that utility is HUMAN NEED. This can now be measured in units of wealth. Utility becomes wealth.
There will be two components of human need: A) Wants and B) Means. The decision making part or brain of any economic identity, ( I call this as utility complex) has both wants and means. To understand this better: imagine utility complex as molecule of water. Water will be in the form of H+ and OH-. There will be equilibrium between wants and means. Now total utility in want terms = total utility in means terms. This applies to nation, state, society or any economic identity.