2012 Ford Focus 1.6 ti vct (105bhp)?

At what rpm in 5th gear would the maximum speed (115mph) be achieved in this model of Focus?

Added (1). I have noticed that in 3rd gear at 3000rpm the car is doing 40mph.

I don't know the exact answer but it would be easy to figure out. Drive your car 58mph (or 57mph) in 5th gear and note the engine RPM at that speed. Then multiply that RPM by 2 to get the RPM the engine would be turning in that gear at twice the road speed. It's literally that simple.

There's a lot more to calculating what the speed would be. Tire size and gear ratio are needed for starters. Then that would give us the RPM in fourth gear - the "Drive" gear. Fifth gear is an overdrive. We'd need to know what ratio that gear is too.

Here's a hint: Go half that speed and read your RPM's. Then double it to get a real close figure as to what it would be.