I have a document (attached link - screendump below) which I have added fields which if ticked, automatically puts the amount owed but if say if the rangers pick up say 2 or more animals, how can I then get the figure to multiply by the number of animals - I guess I would need to add another box to select the number of animals etc but what would the formula be please? I have added the file via Dropbox (I hope it works)...
First of all, there are issues with your code. Also, where is the number of cats, for example, coming from? You could convert the check-box to a text field, and then have the user enter the number of animals into it. In that case you could simply multiply that field's value by the price per animal.
Thanks @try67 - this worked a treat and have changed to a text field and worked a treat. Much easier than my current code.
Check the calculation order of your fields. When in the "Prepare Form" tool use the "More" option to access the "Set Calculation Order".
You could just replace the check mark with a text field set to the "Number" format and then use the entered number to calculate the fee.