Conditional Formatting when cell MAY equal ZERO

This is probably a pretty simple fix, but I have racked my brain for days and just need to get it fixed!

I have a document where I want to divide row B by Row C. About 50% of the time, Row C is going to be a zero, and gives me the #DIV/0 result.

What conditional formula can I use to tell excel to make it first divide Row B by Row C, unless Row C equals zero, in which case divide Row B by .1.

Hopefully that makes sense :-)

Thanks!

Momo