Final answer:
To determine how much Speedy Runner will need to borrow, subtract the ending cash balance from $12,000.
Step-by-step explanation:
To determine how much Speedy Runner will need to borrow at the end of October, we need to know the ending cash balance and the borrowing increments. Since the ending cash balance should be at least $12,000, Speedy Runner will need to borrow the difference between the ending cash balance and $12,000. If borrowing is done in $1,000 increments, we can calculate the borrowing amount as follows:
Borrowing Amount = Ending Cash Balance - $12,000
For example, if the ending cash balance is $13,500, the borrowing amount would be $13,500 - $12,000 = $1,500.
Remember to consider any interest or fees associated with the borrowing.