The car drove evenly over a 3.5 km section of road in 3 minutes. Has the driver violated the traffic rules

The car drove evenly over a 3.5 km section of road in 3 minutes. Has the driver violated the traffic rules if there is a road sign on the side of the road with a speed not exceeding 50 km / h?

To find out if the driver has violated the traffic rules, you need to know the speed of his movement (km per hour). If in 3 minutes the car traveled three and a half kilometers, then in an hour it would have traveled twenty times more (since 60 minutes divided by 3 minutes = 20). Therefore. to find out the speed in a car, you need to multiply the road section 3.5 by 20.
3.5 * 20 = 70.
The speed of the car is 70 km / h, which is more than the permitted 50 km / h, which means that the driver has violated the traffic rules.