From our understanding of work done and kinetic energy, we can write:
F × d = ½ × m × v²
This is a complicated formula, and is normally given for you in the exam - check with your specific syllabus! Usually you just need to know how to use it...
e.g. According to the Highway Code, a car travelling at 31·1 m/s has a braking distance of 75 m. If a car's mass is 1000 kg, what braking force was applied?
F d = ½ m v²