Question

The Regency Hotel has enough space at its entrance for six taxicabs to line up, wait for guests, and then load passengers. Cabs arrive at the hotel every 8 minutes; if a taxi drives by the hotel and the line is full, it must drive on. Hotel guests require a taxi every 5 minutes, on average. It takes a cab driver an average of 3.5 minutes to load passengers and luggage and leave the hotel(exponentially distributed).
1. What is the average time a cab must wait for a fare?
2. What is the probability that the line will be full when a cab drives by, causing it to drive on?

Answer 1

Answer:

The appropriate solution is:

(1) 22.81 minutes

(2) 0.171

Step-by-step explanation:

According to the question, the values will be:

The service rate of guess will be:

= $5+3.5$

= $8.5 \ minutes$

The mean arrival rate will be:

$\lambda =\frac{60}{5}$

  $=7.5 \ cabs/hr$

The mean service rate will be:

$\mu= 7.05 \ cabs/hr$

(1)

The average time a cab must wait will be:

⇒ $W_q=22.95-\frac{1}{7.05}$

⇒       $=\frac{161.798-1}{7.05}$

⇒       $=\frac{160.798}{7.05}$

⇒       $=22.81 \ minutes$

(2)

The required probability will be:

⇒ $P(X\geq 6)=\frac{1-2.115}{1-7.5}$

⇒                  $=\frac{-1.1115}{-6.5}$

⇒                  $=0.171$