speed Calculations

Hi guys ,

i need to do some simple speed calculations in PBP 3 on 18f67k22 pic , that is very very full PIC already.

i have not had to do floating point calculations before and not sure if i need to now for this but i suspect i do, hope i dont cos i believe the overheads can be high .

i have options / variables that select the following for the displayed / recorded results

Display Distance base measurement
00 = Feet
01 = meters
02 = miles
03 = KM

Display Time base measurement
00 = time in sec
01 = time in minutes
02 = Time in Hours
03 = LAP SPEED

Distance input values
0 - 4000

Time input values

days, hours , min, sec , 1/100th


i would like to display the speed for the selected option , with a result to 2 decimal places

can you advise the best way to get this started for the least likely overhead in code space


Cheers

Sheldon