I'll ask you a simple question
@BigNorm , can you count money? If you can, then you can do metric. Everything is divisible by 10. When I taught men/women how to shoot grade in parking lot and highways, 1% grade equals 1 cent (centimeter) per meter (1 dollar),when grading downhill,you pay 1 cent.per dollar, on your grade rod,when you grade uphill, you take 1 cent per dollar. 2%,2 cents so on and so forth. That being said,we still mark with paint on the ground for our operator's in imperial,+1" or -1" and so on,but we know that 25mm,roughly equals 1",50 mm equals 2", it's just WAY EASIER to use metric in civil applications.