I am trying to multiply two custom formula fields so that the answer appears in the third custom field. I also need to divide one of the first custom fields by 100 to reflect decimals. Could you please help me write it out. Here is what I have so far, but it's not working. 

Abs(${Potentials.Total Contract Value}$*({Potentials.Field Contributions (%)}/100*))

Custom field A:  Potentials.Total Contract Value. 

Custom field B:  Potentials.Field Contributions (%)

Answer field: Total Contract Field Contributions

When I also put in the above expression, the syntax error says that "Formula custom fields are not allowed in expression". 

Thanks,

Linda