Final answer:
The main use of the LET statement in QBasic is to assign a value to a variable.
Step-by-step explanation:
In QBasic, the LET statement is used to assign a value to a variable. It is not necessary to use the LET keyword in QBasic, as the assignment can also be done using the equal sign (=) operator. However, using the LET keyword can help improve readability and make the code more understandable.
For example, if you want to assign a value of 10 to a variable named 'x', you can use the LET statement like this: