Is the value in B10 entered directly or via a Drop-down form field?
According to your description, I create a simple table as following.
Besides, each Drop-down form field has a bookmark name like following. Dropdown1 and Dropdown2 have two items "Yes" and "No".
- If it's a number entered manually, in my sample, please try this formula
{if "{Dropdown1}"="Yes" "{=B4*0.2}" "0"}
. You need to use the bookmark name instead of cell name of table, and please replace the B4 with B10, and 0.2 with 20% in yours.
- If you also use a Drop-down form field in B10, in my sample it is Dropdown3, the formula is
{if "{Dropdown1}"="Yes" "{={DropDown3}*0.2}" "0"}
. Please also remember to use the bookmark name.
The results of my sample are shown as below.
Please Note: You need to press Alt + F9 at the same time to switch between Edit Mode with Field Codes. Press Ctrl + F9 at the same time to enter {}, then enter the formula inside the curly brackets.
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