With the help of their meaning you will get the clear idea About their difference
Meaning and Definition of Business report
The business report is a description of business events and financial activities that carries a written presentation in which one analyzes a real situation or a case study of business and applies necessary speculations and/or theories to produce a range of suggestions and/or recommendations in order to improve the situation.
Meaning and Definition of Business letter
A business letter is usually a letter from one company to another, or between such organizations and their customers, clients and other external parties. The overall style of letter depends on the relationship between the parties concerned.