Question

Traffic police measure the speed of the incoming vehicles. The speeds are normally distributed with a mean of 70 km/hr and a standard deviation of 10 km/hr. What percentage of vehicles would-be travelling at random has a speed less than 80 Km/hr?

Answer 1

The required probability is 84.13%

Step-by-step explanation:

Here, x=80

mu= 70

SD=10

So z-value =(80-70)/10 = 1

The probability corresponding to a z value of 1 is 0.8413

So the required probability is 84.13%