The Full Calculation, Worked

Scenario: dry road, good tyres and brakes, 90 km/h, reaction time 1 second. A hazard appears. How far do you travel before standing still?

Reaction distance: 90 → 9; 9 × 1 × 3 = 27 m Braking distance: 90 → 9; 9 × 9 = 81; 81 × 0.4 = 32 m Stopping distance: 27 + 32 = 59 metres.

Nearly sixty metres — twelve car lengths — under ideal conditions with a fast reaction. Every worsening factor from the two stages adds to it from here.

Notice what the two halves are doing. At 90 km/h they're nearly equal (27 and 32). Drop to 30 km/h and reaction dominates completely; climb to 110 and braking runs away with it. That crossover is the whole shape of stopping, and it's why the same driving error costs so differently in town and on the highway.

The method above is how you'd rebuild any stopping figure from scratch — which is exactly what a well-set exam question quietly requires, because tables only list round numbers and questions don't.