Conditional Formulas-to Get A Spreadsheet To Automate Calculations Of Unit Costs Based On Variable Packaging Names

I am looking for a way to get a spreadsheet to automate calculations of unit costs based on variable packaging names.

I have a series of packages that are denoted by text phrases. Examples:

4/6/12
2/12/12
6/4/12
18/12
24/12

For our purposes let's say the package names above will always be in column A. Column B contains the frontline price of a case of product represented by the phrase in column A. Column C will contain the cost per unit of product - this is obtained by dividing column B by the number of each package arrangement that can be found in one case. Most of the time the number of package arrangements per case is denoted by the very first number in the package name (ie, 4/6/12 would be 4). This won't always be the case though (18/12 would be a package arrangement of 1).

I am looking for a way for the spreadsheet to do all of the following and return the results in column C: if the package name contains "4/6/12", divide column B by 4; if the package name contains "2/12/12", divide column B by 2; if the package name contains "6/4/12" divide column B by 6; if the package name contains "18/12", divide column B by 1; if the package name contains "24/12" divide column B by 24.