The width of the carriageway is 9 m, the speed of the student is 1 m / s.

The width of the carriageway is 9 m, the speed of the student is 1 m / s. Will he have time to cross the pedestrian crossing to the green traffic light, the signal of which is on for 20 seconds?

According to the condition of the problem, the distance and speed of the student’s movement are known.

Let’s calculate the time it takes for a student to overcome this distance, dividing the width of the carriageway by the student’s speed:

9: 1 = 9 (sec).

Thus, a student needs 9 seconds to cross a pedestrian crossing, that is, 20 seconds is enough for him.

The answer is yes, that’s enough.