Does the stated dollar amount in a severance package trump the math, even when math is incorrect?

The agreement says that the Employee (me) will be paid the cash equivalent of "Nineteen (6) weeks of Employee's gross base salary. The aforementioned gross dollar amount will be paid to Employee in a lump sum amount, less applicable legal deductions, on the first regularly-scheduled payday after the execution of this Agreement".

The problem is as follows:
A. How many weeks should I expect to be paid for? 19 weeks or 6?
B. The gross amount I get paid is less than the dollar amount stated in the severance package. The dollar amount is showing a vastly lesser total than what I should receive for even 6 weeks. It's off by several thousands of dollars.
C. Even though the severance package states the exact amount it says I should receive the document is severely unclear about how the calculations were made. That being said does the dollar amount stated dictate what I should expect to receive, or does the equation used dictate the amount I should expect?
D. I have already signed this documentation, and am only catching this error today. Do I have any rights to fight this documentation since clearly there is a conflict of statements in the document itself?