Having a problem with finding a sales price per unit.

Well, it depends a whole heck of a lot on the information you've been given. Not giving us any information to work with makes it a bit difficult to try to help you.

If you have total sales and the number of units sold, it's a simple matter of dividing the sales by the units. That would be no different than if you knew you paid $10 for 4 gallons of milk and wanted to know what you paid per gallon. You divide.

A contribution margin ratio is contribution margin divided by sales revenue.