=B2/A2 would give you cost per second. You can either format to a desired
decimal place or use ROUND() to select the number of decimal places to which
you'd like your Round.

"sawahani" wrote:

In a spreadsheet I am composing I have one column that has units of time
(such as :30, or 1:26) and then the next column I have the charges that
occurred in that unit of time (sometimes the units of price are less than a
penny i.e., 0.00015) I would like to divide the unit of time by the charges
to come up with a charge per second average or in some cases exaxctly. How
can I do this?