Calculating Markup For Retail Price

Hello,
I am trying to figure out the formula for calculating retail price if I have the cost and margin (%)/

Example:
cost is $10.00 (known figure)
Markup is : 40% (known figure)
Retail should be: 16.66

Thanks JR

If I understood your question correctly, this should work:

=COST/(1-MARKUP)

Thank you for the help

JR