Answer:
To inform the reader by expanding a body of knowledge that they never knew.
Step-by-step explanation:
The main purpose of a research report is to inform the reader by expanding a body of knowledge that they never knew.
When somebody writes a research paper, a lot of effort of researching things goes into it and the writer explores many questions and answers that he did not know before.
So it is after a lot of researching that the writer of a research report reach to a conclusion by providing the reader information.