One of the interesting cultural differences we have noticed between the US and the UK is in the treatment of billable time, in particular the time currency of charge rates.
In the US, technology businesses traditionally operate time and materials contracts expressing rates in hours while in the UK, day-rates are more frequently used.
In this, our American cousins have the simpler problem to solve when it comes to billing because there is a simple relationship between the time worked and the time billed. All that needs to be considered is the minimum fraction of an hour that is worth billing. More sophisticated time recording systems may introduce the concept of “first fraction and later fractions” to bulk up time charges to a reasonable minimum quantity as no one wants to be billed for 3 ½ minutes, but nevertheless the problem remains relatively straightforward.