Option Button and Check Box

[LFP]

Good morning. I would like to place a check mark in a check box if a certain
option button is checked. I see how I can gray it out to make it
unaccessable but not how I can input the check mark. Anyone know how to do
this?

 

[LFP]

I did figure this out so nevermind... I used a rule that if an option button
= a certain number then I set the check box field to "true"