ANSWER
271 pre-sale tickets were sold.
Step-by-step explanation
Let p represent the number of pre-sale tickets and t represent the number of tickets sold.
According to the question,a total of 800 pre-sale tickets and tickets were sold .
This implies that,

Also the number of tickets sold is 13 less than twice the number of pre-sale tickets.
This gives another equation:

We substitute, the second equation into the first equation to obtain:

This implies that;

Divide both sides by 3

Hence 271 pre-sale tickets were sold.