The time of a call to a technical support line is uniformly distributed between 2 and 10 minutes. What are the mean and variance of this distribution?
A) 6 minutes and 2.3094 (minutes) 2
B) 6 minutes and 5.3333 (minutes) 2
C) 6 minutes and 5.3333 minutes
D) 8 minutes and 2.3094 minutes

Question

The time of a call to a technical support line is uniformly distributed between 2 and 10 minutes. What are the mean and variance of this distribution?
A) 6 minutes and 2.3094 (minutes) 2 
B) 6 minutes and 5.3333 (minutes) 2 
C) 6 minutes and 5.3333 minutes
D) 8 minutes and 2.3094 minutes

Quizplus · Accepted Answer

For a uniform distribution between a and b, the mean is (a+b)/2 and the variance is ((b-a)^2)/12. Here, a=2 and b=10, so the mean is (2+10)/2 = 6 and the variance is ((10-2)^2)/12 = 5.3333.

The Time of a Call to a Technical Support Line