Answer
$ \frac{1}{6}$
Work Step by Step
The probability that the friend is late between 5 and 10 minutes is:
$\frac{1}{30} \times (10 - 5) = \frac{1}{30} \times 5 = \frac{1}{6}$
(Because the value of the random variable is between 0 and 30 the probability for every minute is $\frac{1}{30})$
