Amount Isn't Calculating or Am I Dong it Wrong?

I'm creating a form that sells tickets for $50. I created an "amount" field so the user can enter the amount they would like to purchase. When I enter 3 in the amount field and click "Next" to go to the next page, it shows the amount of $50 and the number of tickets, which is 3. The data shown is correct but;

1. Maybe I'm doing something wrong as I was hoping that when I entered 3 in the "amount" field it would automatically show me the TOTAL of $150 (so the user knows what they are expected to pay). This also means that each time I have to click on "Process Payment" in order to know if the calculations are working correctly. This is my fee formula: [FORM_AMOUNT]*[FIELD_VALUE].

2. Also, I entered a description in the "amount" (pf_amount) field in the back-end but it doesn't show in the front-end, what am I missing?

Any suggestions...

Did you tick the box for the fee field? I forgot to do that and was wondering where my wrong amounts came from.
If you don't sell too many tickets at once, maybe it is more usable if you choose a pull-down list with numbers from 0-9 and aput fees from 0-450 into the fee field. Like this you won't depend on the calculation formula.

Thanks diegom. I see what you mean I missed that.

The total is incorrect. I have this in my fee field [FORM_AMOUNT]*[FIELD_VALUE]. The "Form Amount" is $50 and the "Field Value" I entered is 3. So the total should be $150, but instead the total is showing as $200. I did a test with a couple of other field values and the total is always $50 more than it should be.

I have attached the form and fee fields.

This is from a post in another part of the forum from "mrjansen"

The key is to enable FEE FIELD to YES. I also modified the fee formula to be:
[FORM_AMOUNT]*[FIELD_VALUE]-[FORM_AMOUNT]

I was having the same problem and tried the above remedy and now it is working fine. Hope this helps.

Thanks cscottwoods - really appreciate it!!